DMTDA, dimethyl thio-toluene diamine (CAS 106264-79-3), is a liquid aromatic diamine used as a polyurethane chain extender and epoxy curing agent. Its published specification lists diamines at 95% minimum, water at 0.10% maximum and amine value 515-535 mg KOH/g. Epoxy equivalent weight is 53.6 g/eq. Figure 1. DMTDA as supplied: a light yellow liquid in a glass sample bottle. Product Code: DMTDA Chemical Name: Dimethyl thio-toluene diamine CAS No.: 106264-79-3 Product Category: Aromatic diamine chain extender and epoxy curing agent 1. Introduction DMTDA (CAS 106264-79-3) is a room-temperature liquid aromatic diamine that removes the melt step solid curatives require. Cast polyurethane elastomers and polyurea coatings use aromatic diamines because the rigid ring lifts hardness, modulus and heat resistance above what a polyether amine reaches. The price is reactivity. The published specification is short: appearance, diamine content, toluenediamine (TDA) content, water and amine value. Everything else, from equivalent weight to blend ratio, has to be derived. All numbers come from the public product page. Constants it does not publish are marked calculated, and dosage figures are worked examples. 2. Materials and Methods: DMTDA Identification and Specification The product page publishes five specification items, and DMTDA ships as one liquid grade in drums. 2.1 Product Identification and Specification Table 1 collects the identification data used here, and Table 2 reproduces the published specification. Table 1. Identification data of DMTDA (CAS 106264-79-3). Item Information Product name DMTDA Chemical name Dimethyl thio-toluene diamine CAS No. 106264-79-3 Molecular formula C9H14N2S2 (calculated) Molecular mass 214.3 g/mol (calculated) Amine functionality two primary amines, four active hydrogens Table 2. Published specification of DMTDA, taken from the product page. Item Specification Appearance Light yellow viscous liquid Diamine content 95% minimum TDA content 1.00% maximum Water content 0.10% maximum Amine value 515-535 mg KOH/g 2.2 Test Methods and Data Sources Five items carry published values and the rest are calculated. Appearance is judged visually. Water is determined by Karl Fischer titration according to ASTM E203, and the amine value is obtained by titration and reported in mg KOH/g. The molecular formula and molecular mass are not printed on the product page, so both are calculated and should be confirmed against the current certificate of analysis. Two columns in the later tables are computed rather than measured: amine hydrogen equivalent weight, and the hardener demand that follows. 3. Results and Discussion Reaction with isocyanate is slow for DMTDA, and the reason sits in two methylthio groups. 3.1 Structure and Reactivity of DMTDA Each molecule carries two primary amine groups on a toluene ring, with one methylthio group (–S–CH3) beside each nitrogen. Those sulfur groups are bulky and electron-donating, so the nitrogen lone pair is shielded and the rate of attack on an isocyanate falls. Ring rigidity then raises hardness, modulus and heat resistance in the cured network. The product page states the consequence: the reaction rate with isocyanate is lower than that of DETDA. A slow reaction is not a defect everywhere. In a large casting it extends the pour window; in a small, fast-demould part it costs productivity. The published amine value of 515-535 mg KOH/g is consistent with the calculated mass of 214.3 g/mol. 3.2 Comparison with Alternative Amine Systems Several amine families compete for the same work, and in practice the choice turns on physical state, equivalent weight and reaction rate rather than price per kilogram. DETDA is the closest relative: same diaminotoluene core, also a liquid, and the same polyurea and cast elastomer applications. Its published amine value of 625-640 mg KOH/g is higher, so it carries more amine groups per kilogram and a lower equivalent weight. Less mass is needed per equivalent and the reaction runs faster; DMTDA runs longer, so the two are often blended to set gel time. Alicyclic amines sit at the fast end. 1,2-diaminocyclohexane DACH carries a published AHEW of 28.5 g/eq, roughly double the amine density of DMTDA. m-xylylenediamine MXDA and 1,3-cyclohexanebis(methylamine) are aromatic in character but aliphatic in behaviour. Table 3. DMTDA against alternative amine hardeners, at published and calculated values. Property DMTDA DETDA DACH MXDA 1,3-BAC CAS No. 106264-79-3 68479-98-1 694-83-7 1477-55-0 2579-20-6 Amine value, mg KOH/g 515-535 625-640 900 minimum not published not published Water content, maximum 0.10% 0.10% 0.30% 0.50% 0.30% AHEW, g/eq 53.6 calculated 44.6 calculated 28.5 published 34.1 calculated 35.6 calculated Hardener for EEW 187, phr 28.7 23.8 15.2 18.2 19.0 Read the last row as a cost line. For 100 g of resin, DMTDA needs 28.7 phr, DETDA 23.8 phr and DACH only 15.2 phr, so price per kilogram says little about mix cost. 4. Formulation and Dosage Calculation Hardener demand in an epoxy system comes from one relation: phr = 100 × AHEW ÷ EEW. Four active hydrogens on a molecular mass of 214.3 g/mol give DMTDA an AHEW of 214.3 ÷ 4 = 53.6 g/eq. Table 4. Theoretical DMTDA demand for common liquid epoxy resins. Epoxy resin, published EEW EEW, g/eq DMTDA, phr DETDA, phr Liquid bisphenol A resin YLE-127 176-184 30.5-29.1 25.3-24.2 Liquid bisphenol A resin YLE-128 184-190 29.1-28.2 24.2-23.5 Liquid bisphenol A resin YLE-121 170-176 31.5-30.5 26.2-25.3 Phenolic epoxy resin YLEP-638 170-190 31.5-28.2 26.2-23.5 The resin EEW values come from the liquid bisphenol A epoxy resin grades and the YLEP-638 multifunctional epoxy resin page. Recalculate from the batch EEW. Chain extension is counted differently. The equivalent weight against isocyanate is taken per amine group, so it is 214.3 ÷ 2 = 107 g/eq, calculated. Table 5. Worked chain-extender demand for a cast polyurethane formulation. Parameter Value Prepolymer NCO content 8.0% Isocyanate equivalent weight 525 g/eq NCO equivalents in 100 g prepolymer 0.190 Curative equivalent weight, calculated 107 g/eq Curative at 100% index 20.4 g Index is the lever. A 95% index leaves unreacted isocyanate and a softer part; above 100% the isocyanate is consumed, but unreacted amine can plasticise the elastomer. The right index depends on the hardness target, so verify it on a trial casting. Blending is the second lever. Because DMTDA can be used together with DETDA, the ratio sets both working time and hardness. Start from the equivalent-weight average, then adjust on a gel-time trial. 5. Processing Notes and Operating Window Ambient-temperature liquid means DMTDA can be pumped and metered without a melt tank. Handling rules follow. • Keep the drum closed between uses. Amines take up moisture and carbon dioxide from air, and an open drum drifts past the 0.10% water limit. • Do not heat the drum unless the shop is cold. There is no melting step to justify it, and heat accelerates oxidation. • Watch the blend, not just the two components. If DETDA is added for speed, gel time falls faster than the equivalent-weight average predicts. • Wear nitrile gloves, goggles and a coverall. Aromatic diamines are skin sensitisers, and the safety data sheet carries the PPE list. Figure 2. Metering DMTDA into a polyurethane prepolymer before casting. 6. Applications The product page names three directions: a chain extender and curing agent for polyurethane and polyurea systems, an epoxy curing agent, and an industrial lubricant. Table 6. Application areas for DMTDA and the formulation note for each. Application Role Formulation note Cast polyurethane elastomers chain extender room-temperature or hot casting with an MDI prepolymer Polyurea spraying systems chain extender the slower reaction widens the spray window Other polyurethane products chain extender often blended with DETDA to set demould time Epoxy casting and coatings curing agent requires heat; dosage from the AHEW relation Industrial lubricants functional additive listed on the product page, with no dosage given Figure 3. Polyurea floor coating applied over concrete, a typical end use for DMTDA chain extension. 7. Limitations and Material Verification Three situations call for an amine other than DMTDA. 7.1 Known Limitations and Unsuitable Uses Room-temperature epoxy cure is the first limit. An aromatic amine needs heat for full conversion, so a casting left at 20 °C stays soft in the core. Without an oven cycle or an accelerator, an alicyclic amine such as DACH is the better starting point. Colour is the second, and it matters when the finish is white or light grey. Aromatic amines oxidise in air, so a non-yellowing coating is the wrong place for DMTDA. The third is dosage mass. The high equivalent weight means more hardener mass per kilogram of resin than DETDA or DACH needs. That is a freight cost, not a performance penalty, so quote it per equivalent. 7.2 Incoming Inspection, Packaging, Storage and Safety Four checks catch most incoming-lot problems: appearance against the light yellow reference, water by Karl Fischer titration according to ASTM E203, amine value by titration, and diamine content by the certificate of analysis (COA) method. Run the water check in duplicate on the first drum of each delivery. Drum packaging is standard. Store in a well-ventilated area away from flames and direct sunlight, keep the cap closed after use, and expect a shelf life of at least 12 months from manufacture in the original packing. Safety data sit in the material safety data sheet. Treat the liquid as an irritant and a skin sensitiser, and read the sheet before the first drum is opened. 8. Frequently Asked Questions What is the equivalent weight of DMTDA? For epoxy formulation the amine hydrogen equivalent weight is 53.6 g/eq, calculated as 214.3 g/mol divided by four active hydrogens. For isocyanate chain extension it is taken per amine group and equals 107 g/eq. Confirm both against the current certificate of analysis. How much DMTDA does 100 g of epoxy resin need? For a liquid bisphenol A resin of EEW 187 the theoretical dosage is 100 × 53.6 ÷ 187 = 28.7 phr. The figure moves with the resin: EEW 173 gives 31.0 phr and EEW 250 gives 21.4 phr. Does DMTDA react faster or slower than DETDA with isocyanate? Slower. The product page states that the reaction rate with isocyanate is lower than that of DETDA, which is why DMTDA is described as a slower chain extender. A blend of the two lets a formulator set demould time without changing the stoichiometry. Can DMTDA be processed at room temperature? Handling and metering need no heat, because DMTDA is a liquid at ambient temperature and room-temperature casting of polyurethane elastomers is an established use. Room-temperature epoxy cure is different: an aromatic amine needs heat for full conversion. What is the shelf life and how should DMTDA be stored? At least 12 months from the date of manufacture in the original packing at ambient temperature, according to the product page. Keep the drum closed, in a well-ventilated area away from flames and direct sunlight. A part-used drum left open can fail the 0.10% water limit. Can DMTDA replace a solid aromatic diamine curative? In many cast polyurethane and polyurea systems it can, because a liquid curative removes the melt and hold-temperature steps a solid one requires. It is not a drop-in replacement everywhere: the equivalent weight is higher, so the dosage changes, and the cured colour is darker. 9. Conclusions DMTDA is a liquid aromatic diamine whose published specification covers appearance, diamine content, TDA content, water and amine value, with a calculated amine hydrogen equivalent weight of 53.6 g/eq. Its place in a formulation rests on a pumpable liquid at room temperature, an isocyanate reaction slower than that of DETDA, and the stiffness the aromatic ring gives the cured network. Dosage follows two relations. For epoxy, phr = 100 × AHEW ÷ EEW gives 28.7 phr against a resin of EEW 187. For chain extension, the equivalent weight of 107 g/eq per amine group gives 20.4 g per 100 g of an 8% NCO prepolymer at a 100% index. 10. References 1. Yolatech product page: https://www.yolatech.com/dimethyl-thio-toluene-diamine-dmtda-cas-106264-79-3 (accessed 2026-10-10). 2. Yolatech Technical Data Sheet, Material Safety Data Sheet and Certificate of Analysis for DMTDA, CAS 106264-79-3 (available on request). 3. ASTM E203, water content by Karl Fischer titration. 4. ASTM D1652, epoxy content of epoxy resins (EEW). 5. ISO 3001, determination of epoxy equivalent. 6. ISO 9702, amine group nitrogen content of amine epoxide hardeners.

YLSE-186 epoxy resin is a trifunctional alicyclic epoxy resin, CAS 25293-64-5, that carries one cycloaliphatic epoxide and two glycidyl ester groups on a ring. Its published EEW is 100-111 g/eq at 2000-4000 cps, close to a quarter of liquid bisphenol A viscosity, so it wets fibres without a diluent. Figure 1. YLSE-186 epoxy resin as supplied: a pale straw liquid. Product Code: YLSE-186 / YLSE-186C Chemical Name: 4,5-Epoxytetrahydrophthalic acid diglycidylester CAS No.: 25293-64-5 Product Category: Trifunctional alicyclic epoxy resin 1. Introduction Solvent-free composite work sets two demands against each other. A resin must wet a dry fibre tow easily, yet cure into a stiff matrix. YLSE-186 epoxy resin (CAS 25293-64-5) sits in that gap. All data below come from the public product page for 4,5-epoxytetrahydrophthalic acid diglycidylester. Where the page is silent, figures are marked literature or calculated, and every dosage number can be recomputed. 2. Materials and Methods YLSE-186 ships as a clear to pale yellow liquid in drums, in two commercial grades. Only six parameters are published, so the tables separate measured values from structural inference. 2.1 Product Identification and Specification Table 1 lists the identification data used in this paper, and Table 2 the published specification for both grades. Nothing outside those items is a quality claim. Table 1. Identification data of YLSE-186 epoxy resin (CAS 25293-64-5). Item Information Product Code YLSE-186 (high purity) and YLSE-186C (economy grade) Chemical Name 4,5-Epoxytetrahydrophthalic acid diglycidylester CAS No. 25293-64-5 Epoxy groups per molecule 3: one alicyclic epoxide plus two glycidyl ester groups Appearance Colorless to light yellow liquid, light yellow for YLSE-186C Table 2. Published specification of the two YLSE-186 grades. Item YLSE-186C YLSE-186 Appearance Light yellow liquid Colorless to light yellow liquid Color, Gardner Max. 2 Max. 2 Viscosity, cps at 25 °C 3000-6000 2000-4000 Epoxy equivalent weight, g/eq 100-125 100-111 Volatiles, % Max. 1 Max. 1 Positioning Lower price High purity 2.2 Test Methods and Data Sources Values marked published come from the YLSE-186 product page. Epoxy equivalent weight is determined by titration according to ASTM D1652 or ISO 3001, viscosity is measured at 25 °C, and color according to ASTM D1544. Molecular mass and theoretical EEW are calculated from the structure (Table 3). Table 3. Constants calculated from the YLSE-186 structure. Property Value Basis Molecular formula C14H18O7 Structure Molar mass About 298 g/mol From formula Theoretical EEW About 99 g/eq 298 ÷ 3 Epoxy equivalents per tonne About 10,100 eq At EEW 99 3. Results and Discussion: YLSE-186 Epoxy Resin Reactivity One alicyclic epoxide and two glycidyl ester groups sit on the same cyclohexane ring, and the three sites do not react at the same rate. 3.1 Structure and Reactivity The glycidyl ester groups open faster than the alicyclic ring, and the published description states that reactivity exceeds general alicyclic epoxy resin. Anhydride systems show the split first: ester groups react early, the ring follows at higher temperature. Three sites on one small molecule also give a denser network than a difunctional ester. The theoretical EEW of about 99 g/eq in Table 3 sits just below the published window of 100-111 g/eq, consistent with a small hydrolysis and volatile fraction. Capacity per tonne decides mix economics: at EEW 100 the resin carries about 10,000 equivalents against 5,300 for a bisphenol A resin at EEW 184-190. 3.2 Comparison with Alternative Systems Table 4 compares YLSE-186 epoxy resin with the grades most often quoted against it. Three families compete for this work: difunctional cycloaliphatic esters, trifunctional glycidylamines, and bisphenol A liquids. Table 4. YLSE-186 against alternative epoxy systems, at published values. Property YLSE-186, this grade Alternative grades, published data Epoxy groups per molecule 3: one alicyclic epoxide, two glycidyl ester groups YLCE-2021 cycloaliphatic epoxy resin: 2. YLSE-0600 trifunctional glycidylamine resin: 3. YLSE-721 tetrafunctional epoxy resin: 4 EEW, g/eq 100-111; 100-125 for YLSE-186C YLCE-2021: 126-132. YLSE-0600: 102-110. YLSE-721: 105-120. Liquid bisphenol A epoxy resin YLE-128: 184-190 Viscosity at 25 °C 2000-4000 cps; 3000-6000 cps for YLSE-186C YLCE-2021: 220-250 mPa·s. YLSE-0600: 7000-20000 cps. YLSE-721: 3000-7000 cps at 50 °C. YLE-128: 11000-15000 mPa·s Typical role Solvent-free composite matrix, adhesive base YLCE-2021: thin impregnation. YLSE-0600, YLSE-721: high-crosslink laminating. YLE-128: general purpose. YLEP-638 novolac epoxy resin: hot chemical resistance Read the viscosity column first. YLCE-2021 flows at 220-250 mPa·s, an order of magnitude thinner than YLSE-186, but with only two epoxy groups. Hardener cost is the trade-off buyers miss. Doubling the epoxy equivalents per tonne roughly doubles the amine bought, so a cheap high-functionality grade can lose on mix cost. Price the mix, not the drum. 4. Formulation and Dosage Calculation Amine-cured mixes follow phr = 100 × AHEW ÷ EEW. With YLSE-186 in the 100-111 g/eq window, a hardener of AHEW 96 g/eq is needed at roughly 90 phr, close to double the 50 phr the same hardener asks against a bisphenol A liquid. Table 5. Theoretical hardener demand for an amine of AHEW 96 g/eq. Resin grade, published EEW EEW, g/eq Theoretical hardener, phr YLSE-186 100-111 96.0-86.5 YLSE-186C 100-125 96.0-76.8 Liquid bisphenol A resin YLE-127 176-184 54.5-52.2 Liquid bisphenol A resin YLE-128 184-190 52.2-50.5 The formula is worth checking against published hardener data: YLH-6004 modified amine hardener lists AHEW 96 g/eq and an added weight of 50 phr against a resin of EEW 190, and 100 × 96 ÷ 190 = 50.5. The trap is that 50 phr line. At 50 phr against YLSE-186 you are near half the stoichiometric hardener, so the skin sets hard while the core stays soft. Recalculate from the batch EEW, then confirm with a gel-time check. Anhydride stoichiometry uses a different number: phr = 100 × anhydride equivalent weight ÷ EEW. For a mono-anhydride such as MHHPA anhydride hardener the equivalent weight is about 168 g/eq (calculated), so full stoichiometry at EEW 100 is 168 phr, and most shops run 85-90% of that near 143-151 phr. Viscosity gives one more lever. If 2000 cps is too thick for the mould, blend rather than heat: a glycidyl ester diluent such as YLD-9012 glycidyl ester diluent at 600-1200 mPa·s thins the mix and stays reactive. 5. Processing Notes and Operating Window Three epoxy groups per molecule release more heat per kilogram than a difunctional resin, and the low viscosity moves that heat faster. Exotherm is the first variable to control. • Keep trial mixes near 100 g in a wide container. The same mix in a full pail can gel in a fraction of the time. • Store sealed below 4 °C, and let a cold drum reach room temperature before opening. Condensation goes straight into the resin. • Work in dry air. Alicyclic epoxides hydrolyse slowly, and a humid shop shows up later as a drifting EEW rather than an obvious defect. • De-gas the mixed resin before cure. At 2000-4000 cps it still traps air, and voids in a wound part are expensive to fix. • Wear nitrile gloves, goggles and a coverall. Epoxy resins are skin sensitisers, and the MSDS carries the PPE list. Figure 2. Wet-out of carbon fibre tow in a YLSE-186 resin bath. 6. Applications The product page names two application directions: carbon fibre composites such as high-pressure gas bottles and motor rotors, and high-temperature adhesives. Table 6 sets out what each asks of the resin. Table 6. Application areas for YLSE-186 and the constraint in each. Application What YLSE-186 contributes Where the constraint sits Filament-wound pressure vessels Thin bath for fibre wet-out, more crosslink density per tonne Warm or oven cure; voids if the bath is not de-gassed Motor rotors and rotating parts Stiff matrix with strong fibre binding at a manageable mass Exotherm has to be controlled on thick sections High-temperature adhesives Three reactive sites and a low-viscosity base that accepts fillers Color is loose on YLSE-186C, so use the base grade for visible bond lines Two application lines on a product page are a starting point, not a scope limit. If the part runs through an anhydride bath and needs a stiff matrix, this grade fits; for a cheap filled casting it does not. Figure 3. Filament-wound pressure vessel wound with YLSE-186 epoxy resin. 7. Limitations and Material Verification Two areas limit how YLSE-186 epoxy resin can be specified: the published data set, and the storage behaviour of an alicyclic epoxide. 7.1 Known Limitations The specification covers appearance, color, viscosity, EEW, volatiles and positioning only. Density, flash point, chlorine content, gel time and a titration epoxy value are not on the page, so any dosage plan stays theoretical until a batch COA confirms it, and large neat castings sit outside the grade. 7.2 Incoming Material Verification, Packaging and Safety Drum-to-drum variation exists on any epoxy line, so incoming checks on viscosity, EEW and volatiles are recommended for every lot. Water content is determined by Karl Fischer titration where a lot is disputed, and color is measured according to ASTM D1544. Supply is by drum package, and the page carries two storage statements that do not agree: sealed storage below 4 °C with a shelf life of about six months, and 24 months in original packing. Two numbers that far apart usually describe different conditions, so take the shorter one. Alicyclic epoxides hydrolyse slowly in warm, damp storage: keep drums sealed, use opened drums first, and take hazard information from the Material Safety Data Sheet. 8. Frequently Asked Questions What is the published EEW of YLSE-186 epoxy resin? YLSE-186 is published at 100-111 g/eq and YLSE-186C at 100-125 g/eq. The structure gives a theoretical 99 g/eq, so the window fits a three-functional molecule. Verify the batch value by titration before fixing a ratio. How much hardener does YLSE-186 epoxy resin need per 100 parts of resin? For an amine hardener, phr = 100 × AHEW ÷ EEW. A hardener of AHEW 96 g/eq such as YLH-6004 needs 96.0 phr at EEW 100 and 86.5 phr at EEW 111. Filler load and temperature move the ratio. Can YLSE-186 epoxy resin be cured at room temperature? It can, but slowly. The published description allows amines as a cure route, and the two glycidyl ester groups are the reactive part. Cycloaliphatic epoxies cure slowly with amines in general, so a 15-20 °C workshop cure needs time or a warm post-cure. What is the difference between YLSE-186 and YLSE-186C? Both are the same molecule at the same color ceiling, and the page separates them on price and purity. YLSE-186C has a wider EEW window of 100-125 g/eq and a light yellow tone; YLSE-186 is the high-purity grade at 100-111 g/eq. Can YLSE-186 epoxy resin replace a standard cycloaliphatic epoxy resin? Not as a straight swap. YLCE-2021 carries two epoxy groups at EEW 126-132 g/eq and flows at 220-250 mPa·s, so a substitution changes the hardener ratio and the bath viscosity. YLSE-186 raises crosslink density and roughly doubles the amine charge. Why is YLSE-186 epoxy resin stored below 4 °C? The page instructs storage below 4 °C with a sealed shelf life of half a year, and also repeats the standard line of 24 months in original packing. Plan around the shorter figure: cold storage slows the hydrolysis and color drift of alicyclic epoxides. 9. Conclusions This trifunctional alicyclic epoxy (CAS 25293-64-5) pairs a published EEW of 100-111 g/eq with a viscosity of 2000-4000 cps, so it wets fibre without a diluent and still cures to a high crosslink density. Its practical roles are a solvent-free composite matrix and a base for high-temperature adhesives. Its limits are the thin published data set, a hardener demand near 90 phr with an amine, and a cold, sealed storage requirement. Numbers above are published values or figures marked calculated and literature, and the current TDS / MSDS / COA governs the specification. Grade availability for YLSE-186 epoxy resin is confirmed against a target EEW. 10. References • Yolatech product page, 4,5-Epoxytetrahydrophthalic acid diglycidylester YLSE-186: https://www.yolatech.com/45-epoxytetrahydrophthalic-acid-diglycidylester-ylse-186-cas-25293-64-5 (accessed 2026-10-09). • Yolatech Technical Data Sheet, Material Safety Data Sheet and Certificate of Analysis for YLSE-186, CAS 25293-64-5 (available on request). • ASTM D1652, epoxy content of epoxy resins (EEW). • ISO 3001, determination of epoxy equivalent. • ASTM D445, kinematic viscosity. • ASTM D1544, Gardner color of transparent liquids.

DMAPA curing agent is a colourless primary amine, N,N-Dimethyl-1,3-propanediamine (CAS 109-55-7), that also carries a tertiary nitrogen. Its theoretical AHEW is 51.1 g/eq, so a liquid bisphenol A resin of EEW 190 needs about 27 phr, and this stoichiometry is where most dosage errors begin at mixing. Figure 1. DMAPA as supplied: a water-clear, mobile liquid. Product Code: DMAPA Chemical Name: N,N-Dimethyl-1,3-propanediamine CAS No.: 109-55-7 Product Category: Amine curing agent / functional chemical 1. Introduction Ambient-cure epoxy systems need an amine hardener fast enough for hand-applied coatings yet slow enough to be mixed in a pail, and DMAPA (CAS 109-55-7) sits at the fast end of that range. The data reported here come from the public product page for N,N-Dimethyl-1,3-propanediamine and its published specification. Values the page omits are labelled literature or theoretical. 2. Materials and Methods: DMAPA Curing Agent Grade Data DMAPA is supplied as a colorless liquid in drum packages with a published purity of min. 99.5% and a water limit of max. 0.30%. Only four items are published, so the data below separate published values from structural inference. 2.1 Product Identification and Specification Table 1 lists the identification data used throughout this paper. Table 2 gives the four published specification items; nothing outside it is a quality claim. Table 1. Identification data of DMAPA (CAS 109-55-7). Item Information Product Code DMAPA Chemical Name N,N-Dimethyl-1,3-propanediamine CAS No. 109-55-7 Molecular Formula C5H14N2 (literature) Molecular Weight 102.18 g/mol (literature) Active Hydrogens 2, primary amine only Table 2. Published specification of DMAPA. Item Specification Appearance Colorless liquid Color, APHA Max. 20 Purity Min. 99.5% Water Max. 0.30% 2.2 Test Methods and Data Sources Values marked published come directly from the DMAPA product page. Boiling point, flash point, density and viscosity appear in Table 3 as literature values for CAS 109-55-7 rather than specification limits. Water content is determined by Karl Fischer titration and color is measured according to the APHA scale. Table 3. Physicochemical properties of DMAPA; literature and theoretical values for CAS 109-55-7. Property Typical value Basis Boiling point 132-140 °C at 1013 hPa Literature Flash point About 32 °C, closed cup Literature; ISO 3679 Density About 0.82 g/cm³ at 20 °C Literature Viscosity About 1.2-1.6 mPa·s at 20 °C Literature; ASTM D445 Amine value Not published; about 1098 mg KOH/g theoretical Theoretical; ISO 9702 AHEW 51.1 g/eq theoretical 102.18 ÷ 2 3. Results and Discussion: DMAPA Curing Agent Reactivity DMAPA carries a primary amine and a tertiary amine on one three-carbon chain, and the two nitrogens do different jobs in an epoxy cure. 3.1 Structural Basis of Reactivity The primary amine carries the two active hydrogens, so it alone sets the stoichiometry: 102.18 g/mol divided by two gives a theoretical AHEW of 51.1 g/eq. The tertiary nitrogen has no N-H hydrogen, so it contributes no crosslink and only catalyses the epoxy-hydroxyl reaction, shortening gel time. A short chain with two reactive nitrogens gives a fast, tightly crosslinked and hydrophilic network, so a slow, low-blush room-temperature system is not a realistic target for neat DMAPA. 3.2 Comparison with Alternative Curing Systems Table 4 compares DMAPA with the amine hardeners most often quoted against it, using published figures where a product page states them. Table 4. DMAPA against common amine curing agents, at published or theoretical values. Property DMAPA Common alternatives Active hydrogens / AHEW 2; 51.1 g/eq theoretical DETA 20.6 g/eq; MACM 60 g/eq; YLH-3101 110 g/eq, published Viscosity, published Not published; about 1-2 mPa·s at 20 °C MACM 80-120 mPa·s; YLH-3101 300-1000 cps at 25 °C Water miscibility Miscible MACM insoluble; MXDA soluble; polyetheramine D-230 slightly soluble Blush tendency in humid cure High Lower for water-insoluble amines such as MACM Typical role Co-hardener, accelerator, amidoamine building block DETA, MXDA primary hardeners; MACM high-performance; YLH-3101 modified ready-to-use Color stability of stock Darkens in air once opened DACH also yellows in air; modified grades hold color better For a neat room-temperature coating, DMAPA alone is rarely the right answer. The defensible placement is three roles: an amidoamine building block condensed with fatty or dimer acids, a reactivity booster alongside slower polyetheramines, and a small-dose accelerator where DMP-30 is not wanted. Rigid diamines are another route. 1,3-BAC and MACM trade higher viscosity for water resistance and strength, and N4-AMINE adds a fourth reactive nitrogen for higher crosslink density. If toughness matters more than speed, a polyamide such as YLH-5101 usually out-cures DMAPA on film properties. 4. Formulation and Dosage Calculation Dosage follows the standard amine rule, phr = 100 × AHEW ÷ EEW, which for DMAPA reduces to 100 × 51.1 ÷ EEW because only the two hydrogens on the primary amine count. Table 5. Theoretical DMAPA dosage against published resin EEW values. Resin grade (published EEW) EEW, g/eq Theoretical DMAPA, phr Liquid bisphenol A epoxy resin YLE-128 184-190 26.9-27.8 Liquid bisphenol A epoxy resin YLE-127 176-184 27.8-29.0 Bisphenol F epoxy resin YLE-170 165-175 29.2-31.0 Low-viscosity bisphenol A epoxy resin YLE-121 170-176 29.0-30.1 The error worth guarding against sits in the other nitrogen. If the tertiary amine is counted as active, the same calculation returns 34.1 g/eq and about 18 phr, and the batch gels on top while the underlayer stays soft. Whenever a mix cures unevenly, that arithmetic is the first thing to re-check. A cross-check comes from the same hardener range. YLH-6004 lists AHEW 96 g/eq at 50 phr, and YLH-3101 lists 110 g/eq at 55-60 phr, both against a resin of EEW 190. Treat every value above as a starting point. The working ratio depends on filler loading, resin purity and ambient temperature, and in practice it is confirmed by a gel-time check and a thin-film cure test on about 100 g. 5. Processing Notes and Operating Window Exotherm is the first variable to control: a loading near 27 phr against an EEW 190 resin releases a large amount of heat in a small mass, and the temperature spike shortens working time further. • Keep trial mixes at about 100 g in wide containers; the same mix in a 1 kg pail can gel in a fraction of the time. • Mix cool and post-cure warm. If the film blushes, raise the cure temperature rather than adding more amine. • Watch humidity. Blush forms fastest in cold, damp shops, so schedule amine-cured work away from the wettest part of the day. • Ventilate locally. Keep the drum closed and draw through a pump instead of pouring from an open bung. • Wear nitrile gloves, splash goggles and protective clothing; DMAPA is corrosive and a skin sensitiser, and the MSDS carries the PPE list. • Verify water content on opened drums. Moisture above the 0.30% limit shows up as haze long before a routine COA catches it. Figure 2. Decanting DMAPA under local exhaust ventilation. 6. Applications The product page lists six application directions for DMAPA: cosmetic raw materials, dyestuffs, ion exchange resins, epoxy resin curing agent, non-cyanide electroplating additive, and fibre and leather treatment agent. Table 6 separates the epoxy role from the intermediate roles. Table 6. Application areas for DMAPA and its role in each. Application area Role of DMAPA Practical note Epoxy resin curing Reactive hardener and accelerator About 27 phr against EEW 190 resin; watch blush and exotherm Amidoamine hardeners Amine building block Condensed with fatty or dimer acids Ion exchange resins Amine functionalisation intermediate Amine source for polymer backbones Cosmetic raw materials Intermediate for betaine surfactants An industrial intermediate, not a cosmetic ingredient as supplied Dyestuffs Synthesis intermediate Dye intermediate manufacture Electroplating additive Non-cyanide bath additive Bath formulation is the customer's scope Fibre and leather treatment Treatment agent component Formulated into baths, not applied neat Neat casting in thick sections, food-contact claims, and any specification requiring a published amine value or gel time sit outside what this grade supports on paper. Figure 3. Amine-cured epoxy coating on the internal wall of a steel tank. 7. Limitations and Material Verification Two areas limit how DMAPA can be specified: the published data set itself, and the behaviour of the material in humid air or thick sections. 7.1 Known Limitations The specification covers appearance, color, purity and water only. No gel time, equivalent weight or official amine value is published, so any dosage plan stays theoretical until a batch COA confirms it. Blush is a property rather than a defect, and thick-section casting sits outside the grade because the exotherm of a neat amine in a large mass is hard to control. 7.2 Incoming Material Verification, Packaging and Safety Drum-to-drum variation exists on any amine line, so incoming checks on water content and color are recommended for every lot. Water content is determined by Karl Fischer titration and color is measured according to the APHA scale. DMAPA ships as a drum package with a published shelf life of at least 12 months in unopened packing at ambient temperature. Store in a well-ventilated area away from flames and direct sunlight, and close the cap tightly after each draw. The material is flammable, corrosive and a skin sensitiser; the hazard information is in the Material Safety Data Sheet. 8. Frequently Asked Questions How much DMAPA curing agent is needed per 100 parts of epoxy resin? Divide 5,110 by the resin EEW. The theoretical AHEW of 51.1 g/eq gives about 26.9 phr at EEW 190 and about 31.0 phr at EEW 165. Filler and temperature shift the ratio, so verify by gel time first. Why does the surface of a DMAPA-cured epoxy turn white or stay tacky? Two mechanisms produce that look. A white carbamate film is the amine reacting with CO2 in humid air; a tacky underlayer means under-stoichiometry from counting the tertiary nitrogen as an active hydrogen. Cure warmer and drier, and recalculate at 51.1 g/eq. Can DMAPA replace a modified amine hardener such as YLH-3101 in a floor coating? No, not as a one-for-one swap. YLH-3101 is a modified alicyclic hardener with a published AHEW of 110 g/eq, 55-60 phr loading and a 40-70 min gel time, and its modification exists to control blush. Neat DMAPA cures faster but blushes more. Does the tertiary amine in DMAPA count as an active hydrogen? It does not. The tertiary nitrogen has no N-H hydrogen, so it contributes catalysis but not stoichiometry, and the equivalent weight stays at 102.18 ÷ 2 = 51.1 g/eq. Counting three nitrogens returns 34.1 g/eq and roughly 18 phr, which under-cures the batch. How long can DMAPA be stored, and what does the packing look like? The published shelf life is at least 12 months in the original packing at ambient temperature, supplied as a drum package. No net drum weight is published, so confirm the packing list at order. Opened drums are closed tightly after each draw. Why does DMAPA darken or smoke when a drum is left open? The product page describes the material as flammable and corrosive, one that will smoke and blacken in air. Low-molecular-weight amines absorb water and CO2 quickly, and the reaction shows up as darkening. Keep the cap tight. 9. Conclusions This diamine (CAS 109-55-7) is fast, low-viscosity and water-miscible, and its theoretical AHEW of 51.1 g/eq gives about 27 phr against an EEW 190 resin. Its practical roles are an amidoamine building block, a reactivity booster and a small-dose accelerator. Its limits are humid-cure blush, exotherm in thick sections, and no published gel-time or amine-value data. Values quoted here are published data or figures labelled theoretical and literature; where the product page is silent, the current TDS / MSDS / COA governs. Grade availability for N,N-Dimethyl-1,3-propanediamine DMAPA is confirmed against a target EEW. 10. References • Yolatech product page, N,N-Dimethyl-1,3-propanediamine DMAPA: https://www.yolatech.com/nn-dimethyl-13-propanediamine-dmapa-cas-109-55-7 (accessed 2026-10-09). • Yolatech Technical Data Sheet, Material Safety Data Sheet and Certificate of Analysis for DMAPA, CAS 109-55-7 (available on request). • ASTM D1652, epoxy content of epoxy resins (EEW). • ISO 3001, determination of epoxy equivalent. • ISO 9702, amine group nitrogen content of amine epoxide hardeners. • ASTM E203, water content by Karl Fischer titration. • ASTM D1544, Gardner color of transparent liquids.

Trifunctional epoxy resin YLSE-0600 is a glycidylamine epoxy resin carrying three epoxy groups per molecule at EEW 102-110 g/eq. The resin is a reddish brown liquid of 7000-20000 mPa·s at 25 °C. CAS 71604-74-5. Formulators pick it for high-temperature composites, laminating and structural adhesives. Product Code: YLSE-0600 CAS No.: 71604-74-5 Product Category: Multifunctional epoxy resin, glycidylamine type 1. What YLSE-0600 Is: A Trifunctional Epoxy Resin YLSE-0600 is the Yolatech grade code for a trifunctional epoxy resin built on a 3-glycidyloxy-N,N-diglycidylaniline backbone. CAS 71604-74-5. Two of the three oxirane rings hang on the aromatic nitrogen and the third sits on the phenoxy oxygen, so one molecule offers three amine-reactive sites. Molecular weight works out to 277.3 g/mol from C15H19NO4, which puts the theoretical epoxy equivalent weight at 92.4 g/eq. The product page lists a measured range of 102-110 g/eq. The gap is normal for a glycidylamine made via epichlorohydrin: residual oligomer and hydrolyzable chloride push EEW above theory. If a quote shows EEW below 100 for this CAS number, ask for the lot data behind it. Table 1 gathers the identity data in one place. Item Information Product code YLSE-0600 Chemical name 3-Glycidyloxy-N,N-diglycidylaniline CAS No. 71604-74-5 Epoxy functionality 3 groups per molecule Molecular weight 277.3 g/mol (calculated, C15H19NO4) Theoretical EEW 92.4 g/eq (277.3 / 3) Measured EEW 102-110 g/eq Appearance Reddish brown viscous liquid 2. Published Specifications of YLSE-0600 Five parameters are published for YLSE-0600. Together they define the handling envelope. Item Specification Appearance Reddish brown viscous liquid Color, Gardner Max. 11 Epoxy equivalent weight 102-110 g/eq Viscosity, 25 °C 7000-20000 mPa·s Volatiles Max. 1.0% Two of the five deserve comment. A Gardner color of max. 11 means cured parts will not be water-clear; expect reddish brown castings and films. The viscosity band is also wide, so batch-to-batch flow can drift if your process is tuned tightly. Confirm each lot against the TDS or COA before locking a pump setting or a preheat temperature. 3. Why Three Epoxy Groups Change the Cure Behavior Functionality is the whole story of this resin. DGEBA carries two oxirane rings per molecule; YLSE-0600 carries three, and the tertiary anilinic nitrogen left after glycidylation accelerates the neighboring epoxy-amine reactions. The practical result is a resin that gels faster and builds crosslink density sooner than a bisphenol A grade of comparable viscosity. The product page states the failure mode plainly: even moderate amounts, when cured with aliphatic amines, can develop enough exotherm to char the mass and evolve smoke. That is not boilerplate. A 500 g trial batch of a fast trifunctional epoxy can run away where a 2 kg batch of DGEBA would barely warm. Higher crosslink density usually buys higher glass transition temperature and better hot strength. Yolatech does not publish a Tg figure for YLSE-0600, so treat Tg as formulation-specific: it depends on the hardener, the cure schedule and the post-cure. Verify it on your own laminate before writing a datasheet claim. 4. YLSE-0600 Against Difunctional and Tetrafunctional Alternatives The comparison below uses only parameters published on the Yolatech product pages. Property YLSE-0600 (this resin) YLE-128 (bisphenol A) YLSE-721 (tetrafunctional) Epoxy groups per molecule 3 2 4 EEW, g/eq 102-110 184-190 105-120 Viscosity, mPa·s 7000-20000 at 25 °C 11000-15000 at 25 °C 3000-7000 at 50 °C Color Gardner max. 11, reddish brown not published Gardner max. 10, light yellow Volatiles / water max. 1.0% not published max. 0.6% Backbone aromatic glycidylamine bisphenol A ether aromatic glycidylamine Where does that leave a buyer? If you can heat the resin bath to 50 °C and want maximum crosslink density, YLSE-721 tetrafunctional epoxy resin is the stronger molecule. If you want the lowest hardener demand and the widest supply base, a standard liquid DGEBA is the cheaper answer. YLSE-0600 sits between the two: three epoxy groups per molecule, no heating demanded by the datasheet, and a color that rules out clear finishes. Against a standard liquid DGEBA such as liquid bisphenol A epoxy resin YLE-128, the trade is clearer still: YLSE-0600 asks for far more amine hardener by weight but returns a tighter network. For a phenolic backbone, PNE type phenolic epoxy resin YLEP-631 averages 2.7 epoxy groups per molecule; YLEP-638 semi-solid novolac epoxy resin is its higher-viscosity sibling, usually used in solution. 5. Hardener Dosage: Worked Examples The stoichiometry rule is short: phr = 100 × AHEW / EEW. AHEW values below come from the hardener product pages where published; where a page lists none, the value is theoretical or derived from the amine value. Table 4 covers six hardener families with the dose recalculated at both ends of the resin EEW band. Hardener AHEW, g/eq phr at EEW 102 phr at EEW 110 Source of AHEW Diethylenetriamine DETA 20.6 20.2 18.7 theoretical, 5 active H PACM diamine 52.5 51.5 47.7 theoretical, MW 210.4 / 4 MACM amine hardener 60 58.8 54.5 product page DETDA aromatic diamine approx. 44.6 43.7 40.5 derived from amine value 625-640 mg KOH/g Polyetheramine D-230 approx. 66.7 65.4 60.6 derived from amine value min. 7.5 mmol/g Polyamide hardener YLH-5101 160-200 157-196 145-182 product page For the same DETA on YLE-128 at EEW 184-190 g/eq, the dose drops to about 10.8-11.2 phr. YLSE-0600 therefore consumes roughly 75% more amine by weight per 100 parts resin. That is a real cost line, not a rounding error, and it belongs in your formulation economics next to the gain in crosslink density. Two cautions. These are stoichiometric starting points; in practice many aliphatic-amine systems run at 0.85-0.95 of the theoretical dose to control blush and exotherm. And check the arithmetic against your own certificate of analysis — if the COA says 107 g/eq, use 107, not the midpoint. 6. Cutting Viscosity Without Losing Functionality At 7000-20000 mPa·s, YLSE-0600 wets fiber well but will not self-level at room temperature. Reactive dilution is the standard fix, and the log rule gives a serviceable first estimate: blend viscosity falls roughly geometrically with diluent share. The diluent candidates below are published on the Yolatech site with their own viscosity and EEW. Diluent EEW, g/eq Viscosity, mPa·s Note for use with YLSE-0600 Butyl glycidyl ether YLD-9004A 147-157 max. 2 at 25 °C strongest thinning per part; monofunctional C8-10 alkyl glycidyl ether YLD-7004 220-250 3-10 at 25 °C gentler, needs more parts for the same drop Resorcinol diglycidyl ether YLD-6010 117-129 40-100 at 40 °C aromatic, keeps heat resistance Trimethylolpropane triglycidyl ether YLD-6012 135-145 100-200 at 25 °C trifunctional, preserves network density Pentaerythritol glycidyl ether YLD-6013 125-173 100-800 at 25 °C tetrafunctional character, wider EEW band Take 70 parts of YLSE-0600 at 15000 mPa·s with 30 parts of YLD-6012. The log blend lands near 3300-4100 mPa·s, workable for most impregnation equipment. Blend EEW rises to about 114 g/eq, so the DETA dose falls from 19.4 to 18.0 phr. Both numbers move; recompute both. Dilution is not free. Every part of monofunctional diluent removes reactive sites from the network, and hydrolyzable chloride from the diluent transfers into your system. For electronic work, check the diluent TDS for the chloride line first. 7. Processing Notes and Exotherm Control Batch size is your main exotherm control. • Pre-warm the resin to 40-50 °C before metering if your equipment allows it; as a rule of thumb, epoxy viscosity drops roughly by half for every 10-15 °C of heating. • Keep trial batches under 200 g until the gel behavior of your chosen hardener is known. • Aliphatic amines are the fast path and the fast failure; aromatic amines, MHHPA methyl hexahydrophthalic anhydride with an accelerator, or dicyandiamide systems trade speed for thermal margin. • Mix ratio errors show up as undercure in the core of a casting, not at the surface, so log actual weighed amounts rather than trusting pump settings. • Close the container tightly after drawing; the storage instruction matters more in a humid coastal workshop. When a casting chars or smokes, check batch size first, then hardener choice, then resin quality. In that order. 8. Applications of This Trifunctional Epoxy Resin The product page names six application fields for YLSE-0600: high temperature resistant composites, laminating, resin modification, adhesives, coatings and electronics. Each field below maps to the published data. Application Why this resin fits Numbers behind the judgment High-temperature composites three epoxy groups per molecule build a dense network EEW 102-110 g/eq; viscosity 7000-20000 mPa·s suits preheated impregnation Filament winding and laminating wets fiber after preheat Gardner max. 11 is acceptable on black carbon fiber parts Structural adhesives fast strength build-up with amine hardeners DETA dose approx. 19-20 phr at EEW 106 g/eq Resin modifier small additions raise crosslink density of DGEBA systems 10-30 phr as a modifier is the usual working band Coatings chemical resistance from the aromatic amine backbone plan on pigmentation; the resin itself is reddish brown Electronics used where heat resistance matters more than clarity volatiles max. 1.0% For clear or light-colored work, the honest answer is that Gardner max. 11 is a limitation. YLSE-186 alicyclic glycidyl ester epoxy stays at Gardner max. 2 with EEW 100-111 g/eq, at the price of a different cure profile. For a bisphenol F backbone with lower viscosity, bisphenol F epoxy resin YLE-170 runs 3500-4500 mPa·s but carries only two epoxy groups per molecule. 9. Frequently Asked Questions Can YLSE-0600 replace a bisphenol A resin one for one? No. Swapping YLE-128 for YLSE-0600 roughly doubles the amine dose, from about 11 phr to 19-20 phr of DETA, and gel time shortens. Pot life, exotherm and mix viscosity all move with it. If a plant meters both grades on the same pump, recalibrate the ratio before the first shot. How much amine hardener does YLSE-0600 need? phr = 100 × AHEW / EEW. At the EEW midpoint of 106 g/eq, that gives 19.4 phr for DETA (AHEW 20.6), 49.5 phr for PACM (AHEW 52.5) and 56.6 phr for MACM (AHEW 60). Use the EEW printed on your own COA, not the midpoint; the published band spans 102-110 g/eq. Why does YLSE-0600 cure faster than a bisphenol A epoxy? Three reasons stack up: a third epoxy group per molecule, a tertiary anilinic nitrogen that accelerates the adjacent epoxy-amine reaction, and a low EEW that packs more reactive sites into every 100 g. The downside is heat. Cured with aliphatic amines, even moderate batches can exotherm hard enough to char and smoke, so scale up slowly. Can I thin YLSE-0600 with a reactive diluent? Yes, and the log rule estimates the blend viscosity well enough for pump selection. Roughly 30 parts of YLD-6012 per 70 parts of YLSE-0600 brings 15000 mPa·s down to the 3300-4100 mPa·s range. Butyl glycidyl ether thins harder per part; C8-10 alkyl glycidyl ether needs more. Whatever you pick, recompute the hardener dose from the blend EEW. What is the shelf life and storage condition for YLSE-0600? Shelf life is normally 6 months from the date of manufacture in the original packing at suitable temperatures. Store in a well-ventilated area, keep the drum away from flames and direct sunlight, and close the cap tightly immediately after use. If a drum has sat through a hot summer, check viscosity against the COA before charging the tank. Is YLSE-0600 suitable for clear coatings? It is not. A Gardner color of up to 11 in a reddish brown liquid will read through any clear film. Use it where the part is pigmented, black or hidden inside a laminate. If clarity matters, YLSE-186 with its Gardner limit of 2 is the closer match. 10. Packaging, Storage and Safety YLSE-0600 ships in drum packages. Shelf life is normally 6 months from the date of manufacture in the original packing at suitable temperatures. Store in a well-ventilated area, away from flames and direct sunlight, and close the cap tightly immediately after use. Full safety and handling information is provided in the Material Safety Data Sheet. All parameters quoted here come from the YLSE-0600 product page and should be reconfirmed against the TDS, MSDS or COA of the lot you actually receive. Nothing in this article overrides those documents.

MACM curing agent (3,3'-dimethyl-4,4'-diaminodicyclohexylmethane, CAS 6864-37-5) is a cycloaliphatic diamine epoxy hardener with an AHEW of 60 g/eq. The published grade runs at 99.0% minimum purity with 80-120 mPa·s at 25 °C. Typical dosing is 32-33 phr against a standard 190 g/eq bisphenol A grade. Product Code: MACM (3,3'-Dimethyl-4,4'-diaminodicyclohexylmethane) CAS No.: 6864-37-5 Product Category: Epoxy Curing Agent (Functional Chemical) 1. Product Information Yolatech supplies MACM as a colorless viscous liquid with two primary amine groups on a saturated bicyclic backbone. Figures below come from the product page or the CAS record; anything the page does not publish is marked as such. Item Information Product name MACM Chemical name 3,3'-Dimethyl-4,4'-diaminodicyclohexylmethane CAS No. 6864-37-5 Molecular weight 238.41 g/mol (literature value for this CAS; not published on the product page) Active hydrogens 4 (two primary amine groups, literature structure) Appearance Colorless viscous liquid Color, APHA Max. 30 Viscosity at 25 °C 80-120 mPa·s AHEW 60 g/eq Purity Min. 99.0% Melting point -7 °C (as published) Boiling point 93-100 °C (as published; test pressure not stated) Flash point Above 230 °F (roughly 110 °C) Solubility Insoluble in water; soluble in benzene, ethanol and other organic solvents 2. Product Description: How the MACM Curing Agent Reacts with Epoxy Resins MACM curing agent carries two primary amine groups, so each molecule opens four epoxide rings. Divide the 238.41 g/mol molecular weight by those four active hydrogens and you get 59.6 g/eq, which is why the spec sheet rounds the AHEW to 60 g/eq. Worth repeating on any hardener before you trust a quoted number. The backbone is fully saturated, so the rapid quinone-type yellowing route that aromatic diamines show under UV is not available to MACM. Colour stability in a finished clearcoat still depends on the resin, pigment, UV package and cure schedule. Reaction speed is the trade-off: cycloaliphatic amines react more slowly at room temperature than straight-chain polyamines such as DETA, and formulators close that gap with an accelerator, with heat, or both. 3. Cycloaliphatic Amine Curing Agent Selection: MACM Against the Usual Alternatives MACM sits mid-range: 60 g/eq AHEW, 80-120 mPa·s, APHA 30 maximum. Four other diamines listed on this site bracket it from both sides, and the published data are not equally complete across the five pages. Property (as published) MACM PACM DACH HTDA MXDA CAS No. 6864-37-5 1761-71-3 694-83-7 13897-55-7 1477-55-0 Amine type Cycloaliphatic diamine Cycloaliphatic diamine Cycloaliphatic diamine Cycloaliphatic diamine Arylaliphatic diamine Appearance Colorless viscous liquid Colorless liquid Colorless to light yellow liquid Colorless to light yellow liquid Colorless liquid Viscosity at 25 °C, mPa·s 80-120 50-80 Not published Not published Not published AHEW, g/eq 60 Not published 28.5 Not published Not published Amine value, mg KOH/g Not published Not published Min. 900 820-900 Not published Purity, % Min. 99.0 Min. 99.0 Min. 99.0 Min. 99.0 Min. 99.0 Water, % Not published Max. 0.20 Max. 0.30 Max. 0.10 Max. 0.50 Color limit APHA max. 30 APHA max. 30 APHA max. 30 Gardner max. 1.0 APHA max. 20 Three rows decide most enquiries. Water content is published for PACM, DACH, HTDA and MXDA but not for MACM, so ask for a limit on the COA if your incoming inspection needs one. Amine value appears only for DACH and HTDA; AHEW only for MACM and DACH. If your binding constraint is Reach for Reason Lowest mix viscosity at equal stoichiometry DACH, AHEW 28.5 g/eq Roughly 15 phr against EEW 190, so less hardener goes in Published viscosity window for pump sizing MACM, 80-120 mPa·s PACM is thinner at 50-80 mPa·s but publishes no AHEW Tightest water specification on incoming goods HTDA, max. 0.10% MACM publishes no water figure at all Fastest ambient cure, aromatic backbone accepted MXDA Arylaliphatic amines cure faster than cycloaliphatic ones at 25 °C Flexible, long pot life, low exotherm Polyetheramine D-230 or YLH-6005 AHEW 95 g/eq on YLH-6005 stretches the working window Maximum toughness over chemical resistance YLH-5022 polyamide AHEW 165-185 g/eq, but viscosity runs 30000-80000 mPa·s at 25 °C 4. Typical Technical Information of the MACM Curing Agent Five specification lines is all the product page publishes: appearance, APHA colour, viscosity, AHEW and purity. Density, water content, amine value and gel time are not published; any of those has to come from the TDS or the COA. Item Specification Status Appearance Colorless viscous liquid Published Color, APHA Max. 30 Published Viscosity, mPa·s at 25 °C 80-120 Published AHEW, g/eq 60 Published Purity, % Min. 99.0 Published Density, water content, gel time Not published Request on TDS / MSDS / COA Treat every number here as a specification to confirm against the TDS, MSDS and batch COA, not a performance guarantee. A few mPa·s of viscosity drift between batches is normal; AHEW drift moves your mix ratio directly. 5. Dosage Calculation and Selection Rules Stoichiometric hardener loading follows one equation: phr = 100 × AHEW ÷ EEW. With MACM at 60 g/eq, the whole calculation turns on the epoxy equivalent weight of the resin you actually buy. Resin Published EEW, g/eq MACM at 1:1, phr Hardener share of mix, wt% YLE-128 bisphenol A 184-190 32-33 24.2-24.8 YLE-127 bisphenol A 176-184 33-34 24.8-25.4 YLE-170 bisphenol F 165-175 34-36 25.4-26.5 That number is not fixed. Production formulations usually run 0.9 to 1.1 equivalents of amine hydrogen: excess amine speeds surface cure and raises hardness, a deficit leaves a softer, more chemical-resistant film. Check with your supplier before you move outside 0.95-1.05. One expectation needs correcting early: a 100 mPa·s hardener does not thin a formulation built on YLE-128 at 11000-15000 mPa·s. At 32 phr the hardener is about 24 wt% of the mix, so the blend stays resin-dominated. For sprayable viscosity, change the resin or add a reactive diluent from our reactive diluent range. 6. Processing Notes Amine hardeners fail in predictable ways, and MACM is no exception. What follows is shop-floor practice rather than published specification. - Moisture and carbon dioxide are the usual suspects: an open drum left on a humid floor picks up both, and amine carbonate shows as blush or a greasy film on the cured surface. Close the cap immediately after use. - Weigh the hardener, do not measure it by volume. A 5% shortfall on a 32 phr charge leaves roughly 0.95 equivalents instead of 1.00, and the film will stay soft. - Mix until the streak test is clean. At 80-120 mPa·s against 11000-15000 mPa·s resin, the two phases do not blend by themselves, and unmixed hardener shows up as soft spots days later. - Below roughly 15 °C, ambient cure with cycloaliphatic amines slows to the point of practical failure. Either heat the substrate and the components, or add an accelerator package and re-run your pot-life test. - Pot life depends on mass and temperature, not a fixed number of minutes. A 100 g mix at 25 °C and a 20 kg drum at 35 °C are not comparable; measure both before you commit a shift. - Full property development usually needs a heated post-cure. If your line cannot deliver that, do not write room-temperature-cured properties into the datasheet. 7. Applications Six application areas are published for MACM, split between epoxy curing and non-epoxy synthesis. The epoxy side is where AHEW 60 and the saturated ring matter; the synthesis side only cares about purity and diamine structure. Application Published examples What MACM contributes Watch out for Epoxy adhesives High-grade sanding adhesive, jewellery adhesive Water-clear bond line, low colour drift Thin bond lines cure slowly at 25 °C without an accelerator Epoxy coatings Marine paint, heavy-duty anticorrosive paint, industrial construction paint Chemical resistance with better UV colour hold than aromatic amines Amine blush if the drum has taken up moisture Composites Wind blade, wind mould material, rubber roller Low hardener viscosity helps wet-out before the resin is thickened Exotherm on thick sections; model the mass before you scale up PU and polyurea spray elastomers Amine chain extender and additive Sterically hindered diamine gives controllable reactivity Gel time is formulation-specific; no figure is published for MACM Transparent polyamide and polyimide synthesis Highly transparent nylon, polyimide, polyaspartic acid resin Cycloaliphatic diamine monomer Specify purity min. 99.0% and APHA max. 30 on the order Isocyanate synthesis Raw material Diamine feedstock Water content is not published; agree a limit with us first Coatings formulators usually arrive here from the epoxy resin coatings page, adhesive formulators from epoxy resin adhesives, laminators from epoxy resin composites. The same hardener behaves differently in each, because the binding constraint changes: colour in one, exotherm in another. 8. Frequently Asked Questions What is the AHEW of MACM and how do I turn it into a mix ratio? AHEW is 60 g/eq as published. Divide 100 × 60 by the EEW of your resin: 31.6 phr against a 190 g/eq bisphenol A grade, 35.3 phr against 170 g/eq bisphenol F. Round to one decimal on the batch sheet. Is MACM the same chemical as DMDC? Both names point at CAS 6864-37-5, and both Yolatech pages publish AHEW 60 g/eq with purity min. 99.0%. The MACM page adds a viscosity of 80-120 mPa·s at 25 °C; the DMDC listing calls it a transparent liquid with no viscosity figure. Ask which grade is actually offered before you accept a quotation. Does MACM cure epoxy resin at room temperature? It does, but slowly relative to aliphatic polyamines such as diethylenetriamine DETA. In practice, ambient-cured MACM systems are accelerated or given a heated post-cure, and the schedule should be verified on your own line rather than copied from a datasheet. How much does MACM cut the viscosity of my formulation? Very little, and this is the most common wrong expectation. At 32 phr into a resin of 11000-15000 mPa·s, the blend stays resin-dominated. Lower the viscosity with a resin such as bisphenol F epoxy resin YLE-170 or with a reactive diluent instead. What should I write on the purchase order to lock quality? Three lines cover it: purity min. 99.0%, colour APHA max. 30, viscosity 80-120 mPa·s at 25 °C. If your process is water-sensitive, add a water limit as a fourth line, because the product page does not publish one. Every value should be confirmed on the COA of the shipped batch. When should I choose an anhydride or a polyamide instead? Choose an anhydride such as MHHPA when you need long pot life and high heat distortion with a heated cure. Choose a polyamide such as YLH-5022 when toughness and adhesion to damp concrete matter more than chemical resistance. MACM is not the right pick for either of those priorities. 9. Packaging, Storage and Safety Drum packaging is standard, with a shelf life of at least 12 months from the date of manufacture in the original packing at ambient temperature. Store it in a well-ventilated area, away from flames and direct sunlight, and close the cap tightly immediately after each use. Amines are corrosive and can act as skin sensitisers. PPE, ventilation, spill procedure and first aid are set out in the MSDS, and that document governs your shop floor. Read it before the first drum is opened. Regulatory status deserves one caveat: REACH registration and RoHS conformity for your destination market must be confirmed on the current SDS and supplier declaration before you order, and nothing here should be read as a certification. Ask for written evidence with the batch if an audit needs it. Full specifications, samples and current lead times are on the MACM product page. Related amine hardeners worth comparing include 1,2-diaminocyclohexane DACH, 4,4'-diaminodicyclohexylmethane PACM, methylcyclohexanediamine HTDA, 1,3-cyclohexanebis(methylamine) 1,3-BAC, m-xylylenediamine MXDA, polyetheramine D-230 and modified amine YLH-6005. Resin pairing starts with bisphenol A epoxy resin grades; electrical work is covered under electrical and electronic applications.

Diethylenetriamine DETA, CAS 111-40-0, is a high-purity aliphatic amine curing agent for epoxy systems, supplied at a 99% minimum assay. Two primary and one secondary amine group give fast room-temperature cure in coatings, laminates and adhesives. Standard packing is a 195 kg steel drum or isotank. Product Name: High Purity Diethylenetriamine DETA CAS No.: 111-40-0 Product Category: Curing Agent (Aliphatic Amine) 1. Product Information Diethylenetriamine DETA ships as a colorless to light-yellow liquid in 195 kg drums or isotanks, at a minimum 99% assay with water content limited to 0.50%. The identity data below come from the published product page; reference figures are marked as such and confirmed against the COA for each lot. Item Information Product name High Purity Diethylenetriamine DETA Chemical name Diethylenetriamine (DETA) CAS No. 111-40-0 EC No. 203-865-4 (standard reference) Molecular formula C4H13N3 Molar mass 103.17 g/mol Synonyms 1,4,7-triazaheptane; 2,2'-iminodi(ethylamine) Product category Curing agent (aliphatic amine) 2. Product Description: How Diethylenetriamine DETA Cures Epoxy Resin Diethylenetriamine DETA is an aliphatic ethylene amine with two primary and one secondary amine group, so each molecule offers five active hydrogens for epoxy ring opening. Those five hydrogens give a theoretical amine hydrogen equivalent weight of about 20.6 g/eq, calculated from the 103.17 g/mol molar mass. The reaction is a ring-opening addition between the N-H sites and the epoxide ring, and it runs fast at room temperature while releasing noticeable heat. That exotherm is why small working batches are standard practice on most lines. The product page lists the liquid as strongly alkaline and corrosive to copper and its alloys. It dissolves in water, acetone, benzene, ether and methanol, but not in n-heptane. A high crosslink density follows from the three nitrogen sites, which suits chemical-resistant coatings and adhesives. The same reactivity shortens pot life, though; in practice, open time at room temperature is measured in minutes, not hours. 3. DETA vs Other Amine Curing Agents DETA cures faster than most site-listed amines because its AHEW of about 20.6 g/eq is the lowest in this group, so less hardener is needed per 100 g of resin. The trade-off is a short pot life and a higher exotherm. If a line needs hours of open time, a slower grade from the same catalogue is the safer pick; the table below compares the published figures. Property DETA DACH MXDA MACM DMTDA Structure class Aliphatic triamine Cycloaliphatic diamine Aromatic-side diamine Cycloaliphatic diamine Aromatic diamine CAS No. 111-40-0 694-83-7 1477-55-0 6864-37-5 106264-79-3 Assay or purity Min. 99% Min. 99.0% Min. 99.0% Min. 99.0% Min. 95% Amine value approx. 1630 mg KOH/g (calc.) Min. 900 mg KOH/g not published not published 515-535 mg KOH/g AHEW approx. 20.6 g/eq (calc.) 28.5 g/eq approx. 34 g/eq (calc.) 60 g/eq approx. 44 g/eq (calc.) Water, max 0.50% 0.3% 0.50% not published 0.10% Relative cure speed Very fast Fast Fast Moderate Slow Typical fit Small-batch room-temperature systems Rigid high-heat systems Flexible room-temperature adhesives Toughened structural parts Long-pot-life elastomers Full specifications sit on the product pages for 1,2-diaminocyclohexane DACH, m-xylylenediamine MXDA, MACM, DMTDA and polyetheramine D-230. Polyetheramine D-230, with an amine value of min. 7.5 mmol/g and a molecular weight near 220, sits at the opposite end of the reactivity scale from DETA. 4. Typical Technical Information of Diethylenetriamine DETA The published specification for diethylenetriamine DETA is short: color 20 APHA maximum, assay 99% minimum and water 0.50% maximum, with a colorless to light-yellow appearance. The remaining rows are reference values for CAS 111-40-0 from standard chemical data, marked as literature values. Verify the actual lot against the COA; assay and water shift the effective AHEW by a few percent between batches. Item Value Source Appearance Colorless or light-yellow transparent liquid product page Color, APHA Max. 20 product page DETA content, % Min. 99 product page Water content, % Max. 0.50 product page Molecular formula C4H13N3 literature value Molar mass 103.17 g/mol literature value Theoretical AHEW approx. 20.6 g/eq calculated Boiling point approx. 207 °C literature value Flash point, closed cup approx. 94 °C literature value Density at 20 °C approx. 0.95 g/cm3 literature value Viscosity at 20 °C approx. 7 mPa·s literature value Figures marked as product page data are the published specification; figures marked as literature values or calculated are reference data for orientation only. Confirm all values against the TDS, MSDS and COA before use. 5. Dosage and Mixing Guidance Dosing follows the stoichiometric rule: phr equals AHEW divided by resin EEW, multiplied by 100. With the theoretical AHEW of about 20.6 g/eq, a standard DGEBA epoxy at EEW 185-192 g/eq takes roughly 10.8 phr of diethylenetriamine DETA. A bisphenol F epoxy at EEW 170 g/eq takes about 12.1 phr. Treat these as starting points, not specifications. If the COA AHEW differs from 20.6 g/eq, scale the dose in proportion. Underdosing leaves a tacky surface and weak chemical resistance; overdosing makes the film brittle and raises blush risk in humid weather. Dosage matters. Mix in small batches, because the exotherm accelerates as mass grows. On most lines, 100-200 g working batches keep gel time predictable. Pot life is short. Check with the resin supplier if the system already contains an accelerator, since that shortens open time further. 6. Handling and Processing Notes DETA is corrosive and strongly alkaline, so handling needs the same discipline as any concentrated amine. The points below come from the published storage and safety notes plus standard amine practice. Wear goggles, a face shield, nitrile gloves and a coverall when decanting; skin contact with diethylenetriamine DETA burns. Work with forced ventilation; the liquid has an irritating ammonia-like odor and its vapors irritate airways. Keep away from flames and direct sunlight, because the product page lists the liquid as flammable. Do not use copper or copper-alloy tools, valves or fittings; the amine attacks copper and its alloys. Close the cap tightly immediately after use; amines absorb CO2 and moisture from air and the assay drifts. Decant over a bunded pallet with a drum pump, and flush any spill with plenty of water per the MSDS. 7. Applications Five main fields use diethylenetriamine DETA, from epoxy curing to paper chemicals, because its three nitrogen sites react with many substrates. The epoxy curing line is the volume use on this site; the other four are intermediate roles in downstream products. Field How DETA is used Why the amine structure helps Epoxy curing Room-temperature hardener for coatings, laminates and adhesives Five active hydrogens give high crosslink density at approx. 10.8 phr Wet-strength resin Intermediate for polyamide-epichlorohydrin paper resins Polyamine backbone builds the cationic wet-strength polymer Gas purification Amine scrubbing liquor for CO2 removal Three N-H sites absorb acid gases quickly Lubricant oil additives Intermediate for ashless dispersants Polyamine head anchors to soot and oxidation products Chelating and oil-field chemicals Intermediate for chelants and corrosion inhibitors Multi-nitrogen ligand binds metal ions For formulation background on the epoxy side, see the related notes on epoxy resin coatings and epoxy resin adhesives. Paper mills and gas-treating plants typically buy DETA by the isotank, while coating formulators take the 195 kg drum. If the end use is potable water or food contact, do not assume suitability; check with the compliance team first. 8. Frequently Asked Questions What purity does Diethylenetriamine DETA CAS 111-40-0 carry? The published specification sets assay at 99% minimum, water at 0.50% maximum and color at 20 APHA maximum for diethylenetriamine DETA CAS 111-40-0. The CAS number belongs to the aliphatic ethylene amine family, and the COA for each lot lists the measured assay and water. How much DETA is dosed per 100 g of epoxy resin? Dose by stoichiometry: phr equals AHEW over EEW times 100. With a theoretical AHEW of about 20.6 g/eq, an EEW 190 g/eq bisphenol A epoxy takes about 10.8 phr of DETA. Verify the lot AHEW on the COA and adjust within roughly plus or minus 5%. When should a slower curing agent be chosen instead of DETA? Choose a slower grade when open time of an hour or more is needed, when casting thick sections, or when exotherm control matters. DMTDA at an amine value of 515-535 mg KOH/g, or polyetheramine D-230 at min. 7.5 mmol/g, gives far longer pot life than diethylenetriamine DETA. Is DETA suitable for clear or light-colored coatings? DETA itself is colorless to light-yellow at max. 20 APHA, so fresh films stay light. However, all amine-cured epoxies can yellow under UV and heat aging; if long-term color retention is the priority, test the full system rather than relying on the hardener color alone. How should DETA be stored, and what is its shelf life? Shelf life is at least 12 months from the date of manufacture in the original packing at ambient temperature. Store diethylenetriamine DETA in a well-ventilated area away from flames and direct sunlight, and close the cap tightly immediately after use to limit CO2 and moisture pickup. What safety precautions are required when handling DETA? Treat DETA as a corrosive, strongly alkaline, flammable liquid. Use goggles, a face shield, nitrile gloves and forced ventilation, keep it away from copper alloys, and follow the MSDS supplied with every shipment. 9. Packaging, Storage and Safety Packaging is a 195 kg drum or an isotank, and shelf life is at least 12 months from the date of manufacture in the original sealed packing at ambient temperatures. Store the drums in a well-ventilated area, away from flames and direct sunlight, and close the cap tightly immediately after use. If a drum sits open in humid air, water pickup pushes the 0.50% limit and absorbed CO2 forms a carbamate haze; in practice, re-test assay and water before running an old lot. All safety information is provided in the Material Safety Data Sheet that accompanies every shipment. For samples, current batch COAs, or help choosing between DETA and a slower grade, contact the product team on the diethylenetriamine DETA product page.

Cardanol diglycidyl ether YLD-9014A is a bio-based difunctional epoxy reactive diluent with EEW 200-270 g/eq and a viscosity of 1000-3000 mPa·s at 25°C. The cashew-oil grade cuts high-solid and solvent-free coatings and adhesives while holding film hardness and adding toughness and water resistance. Product Code: YLD-9014A CAS No.: 68390-54-5 Product Category: Diluent & Glycidyl Ether 1. Product Information YLD-9014A ships as a reddish brown liquid in 200 kg drums, with Gardner color max. 18 and water content max. 0.2%. The table below lists the published product data in one place. Item Information Product Code Cardanol Diglycidyl Ether YLD-9014A Chemical Name Cardanol diglycidyl ether, cashew oil modified difunctional glycidyl ether CAS No. 68390-54-5 Appearance Reddish brown liquid Color, G Max. 18 EEW, g/eq 200-270 Viscosity (25°C), mPa·s 1000-3000 Water, % Max. 0.2 Raw material base Cashew oil, plant-derived Packaging 200 kg drum Shelf life 12 months from date of manufacture, original sealed packing 2. Product Description: How Cardanol Diglycidyl Ether YLD-9014A Works Both ends of the cardanol molecule carry a glycidyl group, so YLD-9014A reacts into the cured network instead of evaporating out of it. That single detail is what separates a reactive diluent from a solvent. The backbone pairs a long hydrophobic alkyl chain with a rigid aromatic ring. The supplier describes the result as a balance among film flexibility, impact resistance, and hardness, which is a different promise from a plain flexibilizer that softens the coating to gain toughness. The specification number that separates YLD-9014A from the standard grade is EEW 200-270 g/eq against 290-350 g/eq. A lower epoxy equivalent weight packs more glycidyl groups into each kilogram of liquid, so a given dose of YLD-9014A contributes more crosslinking than the same dose of the standard cardanol diglycidyl ether. In practice that shows up as higher reactivity and a tighter cured network. When a formulation is short on cure speed or heat resistance, the lower-EEW grade buys some back without giving up the cardanol flexibility. It can be run blended into conventional epoxy resins, or as the standalone resin when flexibility is the priority. The raw material is a plant extract rather than a petrochemical feedstock, and the grade is presented as renewable and non-toxic. That helps in export markets where VOC reduction and bio-content carry weight in the specification. 3. YLD-9014A vs Alternative Reactive Diluents The realistic alternatives are the standard cardanol grade in the same family and the low-viscosity monofunctional ethers. Published specifications settle most of the choice before a trial batch is even mixed. Property YLD-9014A YLD-9014 YLD-9016 YLD-9006 BGE YLD-9004A Functionality Difunctional Difunctional Bifunctional Monofunctional Monofunctional EEW, g/eq 200-270 290-350 250-330 355-500 147-157 Viscosity (25°C), mPa·s 1000-3000 1000-3000 60-150 30-50 Max. 2 Raw material base Cashew oil, bio-based Cashew oil, bio-based Cashew oil, bio-based Cashew oil, bio-based Petrochemical Typical role Reactivity plus toughness in coatings and adhesives Standard general-purpose toughener-diluent High-flexibility, ultra-low viscosity Low-viscosity monofunctional diluent Fast, low-cost viscosity cut Every reactive diluent is a trade-off: flexibility and water resistance climb while Tg and hardness come down. If a film has to stay hard while you add impact resistance, the flexible-rigid balance of cardanol diglycidyl ether YLD-9014A fits better than a soft flexibilizer. When the job is a deep viscosity cut, the numbers are blunt. Cardanol diglycidyl ether YLD-9016 sits at 60-150 mPa·s and cardanol glycidyl ethers YLD-9006 at 30-50 mPa·s. YLD-9014A, at 1000-3000 mPa·s, is not the tool for that. Against petrochemical ethers, the honest comparison is odor and property retention. A butyl glycidyl ether BGE YLD-9004 thins faster and costs less per liter, but the cardanol grades are positioned as lower-odor options with less damage to cured thermal properties. For projects that also carry a halogen-free or low-odor requirement, that usually decides the argument. 4. Typical Technical Information of Cardanol Diglycidyl Ether YLD-9014A Cardanol diglycidyl ether YLD-9014A is specified by five published parameters: appearance, Gardner color, epoxy equivalent weight, viscosity, and water content. The values below are specification ranges, not batch certificates. Item Specification Appearance Reddish brown liquid Color, G Max. 18 EEW, g/eq 200-270 Viscosity (25°C), mPa·s 1000-3000 Water, % Max. 0.2 Confirm the current batch against the TDS, MSDS, and COA before releasing a formulation, and re-check EEW on incoming material if the hardener ratio is calculated tight. 5. Formulation and Selection Guidance Cardanol diglycidyl ether YLD-9014A carries epoxy groups of its own, so it consumes hardener like any other epoxide. Blend EEW = 1 / (w1/EEW1 + w2/EEW2), then hardener phr = 100 × AHEW / blend EEW. Worked example. Take 90 parts of a bisphenol F epoxy resin at EEW 170 plus 10 parts YLD-9014A at its EEW midpoint of 235 g/eq. Blend EEW = 1 / (90/170 + 10/235) = 175 g/eq. With a dicyandiamide-type hardener at AHEW 60, demand is 100 × 60 / 175 = 34.3 phr, against 35.3 phr for the neat resin. Treat 34.3 phr as a starting point, not a specification, because the exact figure depends on the accelerator package and cure schedule. Viscosity moves less than reactivity does, because YLD-9014A sits at 1000-3000 mPa·s itself. A log-rule estimate for 10 parts YLD-9014A taken at 2000 mPa·s in 90 parts of a 15,000 mPa·s resin lands near 12,300 mPa·s, roughly an 18% cut. If a line has to get under 1000 mPa·s, the ultra-low-viscosity grades are the correct pick instead. On dosage, most formulators start cardanol diglycidyl ether YLD-9014A at 5-15 phr against standard liquid epoxy resins. Above roughly 20 phr the network softens noticeably; check heat-deflection data on the actual system before committing to a level. We can supply grade-matched TDS data on request. 6. Processing Notes Field experience with cardanol diglycidyl ether YLD-9014A reduces to a short list: Add the diluent to the resin first and homogenize before dosing the hardener; adding it after the amine invites local stoichiometry errors. Cold warehouses push viscosity toward the top of the 1000-3000 mPa·s window. In practice, check viscosity at room temperature, not straight off a winter pallet. The reddish brown tone (Color max. 18) shows through light-colored topcoats. When color is critical, a paler grade such as YLD-9016 (max. 12) is the better fit. Batches differ inside the published ranges. If the hardener ratio is calculated tight, feed incoming COA values into the phr math rather than last year's averages. Amine adducts prepared on a difunctional ether usually gel a little differently from those on monofunctional ethers; run a gel-time check before locking pot life. Store cool, dry, and out of direct sunlight, and keep drums sealed because glycidyl ethers pick up moisture slowly in humid climates. 7. Applications YLD-9014A earns its place where viscosity, toughness, and water resistance have to move together. Typical uses reported for the grade: Application Role of YLD-9014A Structural and general adhesives Raises bond strength and flexibility while limiting loss of mechanical strength High-solids coatings Viscosity reduction with lower VOC emissions Solvent-free (2K) systems Reactive diluent that co-cures instead of evaporating Composites and FRP Toughening agent and impregnation aid in winding and pultrusion lines Modified curing agents Building block for amine adducts The same logic runs across the families documented in epoxy resin adhesives and epoxy resin coatings: wherever a brittle network fails in wet or impact service, the cardanol backbone is worth a trial. For structural work, see epoxy resin composites. 8. Frequently Asked Questions What is cardanol diglycidyl ether YLD-9014A used for? YLD-9014A works as a reactive diluent and toughening agent in epoxy adhesives, high-solids and solvent-free coatings, composites, and amine adduct curing agents. It cuts blend viscosity while adding flexibility, water resistance, and adhesion strength. What is the CAS number of YLD-9014A? CAS No. 68390-54-5 belongs to cardanol diglycidyl ether YLD-9014A. The sibling grades YLD-9014 and YLD-9016 share the same CAS, since they carry the same cardanol diglycidyl ether chemistry but different EEW and viscosity windows. How is YLD-9014A different from YLD-9014? Both are difunctional cardanol diglycidyl ethers in the same 1000-3000 mPa·s band. The difference is EEW: YLD-9014A runs 200-270 g/eq against 290-350 g/eq for YLD-9014. The lower value means more epoxy groups per kilogram, so YLD-9014A cures more reactively and builds a tighter network. Choose the standard grade when you want the maximum flexibility and the lowest reactivity, and YLD-9014A when reactivity or hardness retention matters more. How much YLD-9014A should I add to an epoxy formulation? Most systems start between 5 and 15 phr. The right level depends on how much flexibility you can trade against Tg: above roughly 20 phr, hardness and heat resistance drop noticeably. Verify the final dosage against your own cure schedule. Can YLD-9014A be used as a standalone resin? Yes. YLD-9014A can run as a modifier in conventional epoxy systems or as the standalone resin when flexibility is the priority. Standalone use is not the right choice for neat casting that needs high rigidity, because the cardanol backbone keeps the cured part flexible by design. How should YLD-9014A be stored and how long does it last? Store in a cool, dry place away from direct sunlight with drums sealed. Shelf life is 12 months from the date of manufacture in the original packing at ambient temperature. All safety handling details are provided in the MSDS. 9. Packaging, Storage and Safety Packaging is a 200 kg drum. Shelf life is 12 months from the date of manufacture in the original sealed packing at ambient temperatures. Store in a cool and dry place and avoid direct sunlight. Keep containers closed when not in use, because most glycidyl ethers slowly absorb moisture in humid storage. All safety information is provided in the Material Safety Data Sheet that accompanies every shipment and is available on request. For samples, current batch COAs, or help matching a grade to a viscosity target, contact the product team on the YLD-9014A product page or browse the full range on the diluent and glycidyl ether category page.

Cardanol diglycidyl ether YLD-9014 is a bio-based difunctional epoxy reactive diluent with EEW 290-350 g/eq and a viscosity of 1000-3000 mPa·s at 25°C. The cashew-oil derived molecule cuts viscosity in high-solids coatings and adhesives while adding toughness, moisture resistance, and bond strength. Product Code: YLD-9014 CAS No.: 68390-54-5 Product Category: Diluent & Glycidyl Ether 1. Product Information The grade ships as a reddish brown liquid in 200 kg drums, with Gardner color max. 18 and water content max. 0.2%. The table below collects the published product data in one place. Item Information Product Code Cardanol Diglycidyl Ether YLD-9014 Chemical Name Cardanol diglycidyl ether, cashew oil modified difunctional glycidyl ether CAS No. 68390-54-5 Appearance Reddish brown liquid Color, G Max. 18 EEW, g/eq 290-350 Viscosity (25°C) 1000-3000 mPa·s Water content Max. 0.2% Packaging 200 kg drum Shelf life 12 months from date of manufacture, original sealed packing 2. Product Description: How YLD-9014 Toughens Epoxy Systems Chemically, cardanol diglycidyl ether YLD-9014 is a cashew oil modified difunctional glycidyl ether. Two glycidyl groups sit on a long-alkyl cardanol backbone, so the molecule co-reacts into the cured network instead of staying in it as a free plasticizer. That is the difference between a reactive diluent and a solvent. The long hydrophobic alkyl chain does three jobs at once. It drops the blend viscosity so high-solids and solvent-free systems can be pumped, mixed, and wetted out. It internal-plasticizes the network, which is where the flexibility and impact resistance come from. And it repels water, so cured films keep their properties in wet service better than many petrochemical-diluent systems. One more practical point. Cardanol-based diluents tolerate imperfect surfaces: when the substrate carries traces of moisture or light oil, YLD-9014-based formulations hold adhesion where a brittle neat resin would peel. Surface preparation still matters, but the margin is wider. Compatibility with conventional epoxy systems is built in, and YLD-9014 can also be used as a standalone resin when flexibility outweighs hardness. It is derived from botanical extracts, a renewable and non-toxic raw material base, which helps with VOC and labeling discussions in export markets. 3. YLD-9014 vs Alternative Reactive Diluents The main alternatives are the low-viscosity monofunctional ethers and the other cardanol grades in the same family. The table below compares published specifications side by side. Property YLD-9014 YLD-9014A YLD-9016 YLD-9006 BGE YLD-9004A Functionality Difunctional Difunctional Bifunctional Monofunctional Monofunctional EEW, g/eq 290-350 200-270 250-330 355-500 147-157 Viscosity (25°C), mPa·s 1000-3000 1000-3000 60-150 30-50 Max. 2 Raw material base Cashew oil, bio-based Cashew oil, bio-based Cashew oil, bio-based Cashew oil, bio-based Petrochemical Typical role Toughener-diluent for adhesives and composites Flexible-rigid balance in coatings Low-viscosity AGE/BGE alternative General diluent, low odor Fast viscosity cut Every reactive diluent is a trade-off: flexibility and water resistance go up, while Tg and hardness come down. If your formulation needs film hardness more than flexibility, cardanol diglycidyl ether YLD-9014A is the closer match; it balances flexible and rigid segments and holds impact resistance without going soft. If the job is a deep viscosity cut instead, the numbers above say it plainly. Cardanol diglycidyl ether YLD-9016 sits at 60-150 mPa·s, and cardanol glycidyl ethers YLD-9006 at 30-50 mPa·s. YLD-9014, at 1000-3000 mPa·s, is not the tool for that. Against BGE, the honest comparison is odor and property retention. A butyl glycidyl ether BGE YLD-9004 blend thins faster and costs less per liter, but the cardanol grades are widely positioned as non-toxic alternatives to AGE and BGE, with less impact on cured thermal properties and no irritating odor. In export projects with RoHS-style halogen-free and low-odor requirements, that usually decides the argument. 4. Typical Technical Information of Cardanol Diglycidyl Ether YLD-9014 Cardanol diglycidyl ether YLD-9014 is specified by five published parameters: appearance, Gardner color, epoxy equivalent weight, viscosity, and water content. The values below are the published specification ranges. Item Specification Appearance Reddish brown liquid Color, G Max. 18 EEW, g/eq 290-350 Viscosity (25°C), mPa·s 1000-3000 Water, % Max. 0.2 Treat these as specification ranges, not batch certificates. Confirm the current batch against the TDS, MSDS, and COA before you release a formulation to production, and re-check EEW on incoming material if your hardener ratio is calculated tight. 5. Formulation and Selection Guidance YLD-9014 carries epoxy groups of its own, so it consumes hardener like any other epoxide. The stoichiometry is straightforward. blend EEW = 1 / (w1/EEW1 + w2/EEW2), then hardener phr = 100 × AHEW / blend EEW. Worked example. Take 90 parts of a bisphenol F epoxy resin (EEW 170, such as the site's bisphenol F epoxy resin grade) plus 10 parts YLD-9014 at its EEW midpoint of 320 g/eq. Blend EEW = 1 / (90/170 + 10/320) = 178 g/eq. With a dicyandiamide-derivative hardener at AHEW 60, demand is 100 × 60 / 178 = 33.7 phr, versus 35.3 phr for the neat resin. The exact number depends on your accelerator package and cure schedule; treat 33.7 phr as a starting point, not a specification. Viscosity responds fast but not dramatically, because YLD-9014 itself sits at 1000-3000 mPa·s. A log-rule estimate for 10 parts YLD-9014 (taken at 2000 mPa·s) into 90 parts of a 15,000 mPa·s resin gives roughly 12,300 mPa·s, an 18% cut. If your line needs to get below 1000 mPa·s, YLD-9016 is the grade built for that, not YLD-9014. As a starting window, most formulators run YLD-9014 at 5-15 phr against standard liquid epoxy resins. Above roughly 20 phr the network softens noticeably; check the heat-deflection numbers on your own system before committing. We can supply grade-matched TDS data on request. 6. Processing Notes Field experience with cardanol diglycidyl ether YLD-9014 boils down to a short list: Add the diluent to the resin first and homogenize before dosing the hardener; adding it to the mix after the amine invites local stoichiometry errors. Cold warehouses push viscosity toward the top of the 1000-3000 mPa·s window. In practice, check viscosity at room temperature, not straight off a winter pallet. Amine adducts prepared on YLD-9014 usually cure a little slower than adducts on monofunctional ethers; plan pot life and post-cure accordingly. The reddish brown tone (Color max. 18) will show through light-colored topcoats. When color is critical, YLD-9016 (max. 12) is the paler choice. Batches differ inside the published ranges. If your hardener ratio is calculated tight, run incoming COA values into the phr math rather than last year's averages. Storage is cool, dry, and out of direct sunlight; keep drums sealed because glycidyl ethers pick up moisture slowly in humid climates. 7. Applications YLD-9014 earns its place where viscosity, toughness, and water resistance must move in the same direction. Typical uses reported for the grade: Application Role of YLD-9014 Structural and general adhesives Raises bond strength and flexibility while limiting loss of mechanical strength High-solids coatings Viscosity reduction with lower VOC emissions Solvent-free (2K) systems Reactive diluent that co-cures instead of evaporating Composites and FRP Toughening agent and impregnation aid in winding and pultrusion lines Modified curing agents Building block for amine adducts The same logic extends across the product families documented in epoxy resin adhesives and epoxy resin coatings: wherever a brittle network fails in wet or impact service, the cardanol backbone is worth a trial. For structural composites, see epoxy resin composites. 8. Frequently Asked Questions What is cardanol diglycidyl ether YLD-9014 used for? YLD-9014 works as a reactive diluent and toughening agent in epoxy adhesives, high-solids and solvent-free coatings, composites, and amine adduct curing agents. It cuts blend viscosity while adding flexibility, water resistance, and adhesion strength. What is the CAS number of YLD-9014? Cardanol diglycidyl ether YLD-9014 has CAS No. 68390-54-5. The same CAS applies to the sibling grades YLD-9014A and YLD-9016, which share the cardanol diglycidyl ether chemistry but differ in EEW and viscosity windows. How much YLD-9014 should I add to an epoxy formulation? Most systems start between 5 and 15 phr. The right level depends on how much flexibility you can afford to trade against Tg: above roughly 20 phr, hardness and heat resistance drop noticeably. Verify the final dosage with your own cure schedule. What is the difference between YLD-9014 and YLD-9014A? Both are difunctional cardanol diglycidyl ethers at 1000-3000 mPa·s. YLD-9014A has a lower EEW window (200-270 g/eq versus 290-350 g/eq) and combines flexible and rigid segments, so it holds film hardness and impact resistance better; YLD-9014 is the tougher, more flexible choice. Does YLD-9014 slow down the epoxy cure? The glycidyl groups are reactive, so the network cures normally, but amine adducts built on YLD-9014 usually set a little slower than those on monofunctional ethers. If cycle time is tight, run a DSC or gel-time check on your own hardener package before locking the recipe. How should YLD-9014 be stored and how long does it last? Store in a cool, dry place away from direct sunlight, drums sealed. Shelf life is 12 months from the date of manufacture in the original packing at ambient temperature. All safety handling details are provided in the MSDS. 9. Packaging, Storage and Safety Packaging is a 200 kg drum. Shelf life is 12 months from the date of manufacture in the original sealed packing at ambient temperatures. Store in a cool and dry place and avoid direct sunlight. Keep containers closed when not in use; like most glycidyl ethers, the material slowly absorbs moisture in humid storage. All safety information is provided in the Material Safety Data Sheet, which accompanies every shipment and is available on request. For samples, current batch COAs, or help matching a grade to your viscosity target, contact the product team on the YLD-9014 product page or browse the full diluent range on the diluent and glycidyl ether category page.

Cardanol glycidyl ether YLD-9006 is a bio-based monofunctional reactive diluent with viscosity 30-50 mPa·s at 25 °C and EEW 355-500 g/eq. It thins epoxy coatings, adhesives and potting compounds, and it comes from cashew nut shell liquid (CNSL). It carries one epoxide group on a C15 aliphatic chain.   Product Code: YLD-9006 — Cardanol Glycidyl Ether, monofunctional reactive diluentKey Raw Material: Cardanol from cashew nut shell liquid (CNSL) — CAS No. 171263-25-5Product Category: Reactive Diluent / Glycidyl Ether (Diluent & Glycidyl Ether line) 1. Product Information Item Information Product Name Cardanol glycidyl ethers YLD-9006 Chemical Family Glycidyl ether of cardanol, a C15 phenolic alcohol distilled from cashew nut shell liquid CAS No. 171263-25-5 Epoxide Functionality 1 — the product page describes YLD-9006 as a single epoxy-based active diluent Appearance Transparent liquid Primary Use Viscosity reduction in coatings, adhesives, potting and casting compounds, and composites Packaging Drum 2. Product Description: What Cardanol Glycidyl Ether YLD-9006 Does in an Epoxy System Cardanol glycidyl ether YLD-9006 is a reactive diluent, so it cures into the network instead of evaporating from the film. One epoxide group sits at the end of a C15 aliphatic chain, and that structure explains most of what you see at the bench. A single epoxide pushes the EEW up to 355-500 g/eq, which is high for a diluent, while the same long chain holds viscosity at 30-50 mPa·s at 25 °C. BGE reaches 147-157 g/eq by comparison, so the two products are not interchangeable gram for gram. Cardanol is distilled from cashew nut shell liquid, which makes YLD-9006 a renewable feedstock product rather than a petrochemical one. The phenol ring carries a C15 side chain that occurs naturally as a mixture of saturated, monoene, diene and triene forms. That mixture is why two drums of the same grade can differ slightly in colour and EEW, and why incoming EEW checks pay for themselves. Against fatty-chain monofunctional glycidyl ethers, the product page reports less impact on the thermal properties of the cured material, a clear toughening effect, and no irritating odour. The C15 chain acts as a built-in flexibilizer, so one additive delivers both viscosity reduction and impact improvement. YLD-9006 mixes well with aliphatic and aromatic epoxy resins, so it can be dropped into an existing high-solids coating or electronic potting formula without a compatibilizer. The product page also lists modified curing agents, a smaller outlet that few buyers ask about. 3. YLD-9006 Compared with Conventional Reactive Diluents Four diluents cover most of the market, and they are not interchangeable by weight because their epoxide contents differ threefold. The table below uses published data from the Yolatech product pages for each grade, so every row can be checked at source. Read the EEW column first, then viscosity; the first sets hardener consumption, the second sets how far it can thin a system. Attribute YLD-9006 (cardanol mono) YLD-7004 (C8-10 AGE) YLD-9004A (BGE) YLD-9014 (cardanol di) Epoxide groups 1 1 1 2 EEW, g/eq 355-500 220-250 147-157 290-350 Viscosity at 25 °C 30-50 mPa·s 3-10 mPa·s max 2 mPa·s 1000-3000 mPa·s Appearance Transparent liquid Transparent, APHA max 40 Transparent, APHA max 20 Reddish brown, colour G max 18 Hydrolyzable chloride max 0.5% max 0.2% max 0.1% not published Water max 0.1% max 0.1% max 0.5% max 0.2% Feedstock base CNSL, renewable C8-C10 synthetic alcohol Butanol CNSL, renewable Thermal effect on cured resin Less impact than fatty-chain mono diluents (supplier claim) Reference product for that claim Shortest chain, largest Tg drop Difunctional, adds crosslink density Toughening behaviour C15 chain flexibilizes Moderate None to slight High flexibility grade of the series Typical fit High-solids coatings, electronic potting Low-cost viscosity control Fast viscosity knock-down Flexible adhesives and sealants Weight-for-weight substitution is the most common mistake. Fifteen phr of BGE carries roughly 0.10 equivalents of epoxide, while the same loading of YLD-9006 carries about 0.04, so a straight swap leaves the mix under-cured unless the hardener is recalculated. If the requirement is crosslink density rather than viscosity, the monofunctional YLD-9006 is the wrong tool. Move to a cardanol diglycidyl ether YLD-9014 or the higher-flexibility cardanol diglycidyl ether YLD-9016, both of which carry two epoxide groups on the same renewable backbone. For a cost-driven viscosity cut on an unexposed substrate, a butyl glycidyl ether BGE YLD-9004 or a C8-10 alkyl glycidyl ether YLD-7004 costs less per unit of reduction. Workplace rules usually decide the rest. Many formulators have moved away from BGE for handling reasons rather than technical ones, so check the current SDS and your local exposure limits first. 4. Typical Technical Information of Cardanol Glycidyl Ether YLD-9006 The table below is the published specification for YLD-9006 and doubles as an incoming-inspection checklist. Item Specification Appearance Transparent liquid Viscosity at 25 °C 30-50 mPa·s EEW, g/eq 355-500 Hydrolyzable chloride Max. 0.5% Inorganic chlorine Max. 200 mg/kg Water Max. 0.1% Shelf life At least 12 months in original packing at ambient temperature These are typical values from the product page. Verify each lot against the TDS, MSDS and COA, and treat the EEW band as a range that drives hardener calculation rather than a fixed number. 5. Formulation and Selection Guidance A reactive diluent changes the epoxide equivalent weight of the blend, and the hardener dose follows that number. For two epoxy-bearing streams the mixing rule is simple: blend EEW = total mass divided by total epoxide equivalents. Hardener then follows phr = 100 × AHEW ÷ blend EEW, using the AHEW printed on the curing agent data sheet. Take a bisphenol F epoxy resin at EEW 170 g/eq and 3500-4500 mPa·s as the base, with a DMDC curing agent CAS 6864-37-5 at AHEW 60 g/eq as the hardener. Compare three blends at 15 phr diluent loading. Epoxy side Blend EEW, g/eq DMDC, phr Bisphenol F resin alone 170 35.3 Plus 15 phr YLD-9006 184 32.6 Plus 15 phr BGE YLD-9004A 167 35.8 The numbers use the mid-point of each published EEW band: 400 g/eq for YLD-9006 and 152 g/eq for BGE. Because YLD-9006 consumes less hardener per gram, a 15 phr addition lowers the DMDC demand by about 2.7 phr against the neat resin. That is a real cost offset that most buyers miss. Start at 5 phr and step up in 5 phr increments. Most formulators stop between 10 and 20 phr, because above that the monofunctional fraction acts as a plasticizer and pulls hardness, chemical resistance and glass transition temperature down. Viscosity does not fall in a straight line. A log-mixing estimate for the 15 phr blend above lands near 2000-2500 mPa·s at 25 °C, down from 3500-4500 mPa·s for the neat resin. Estimate only — in practice, confirm it with a laboratory reading on your own resin lot, since temperature and shear history both shift the result. 6. Processing Notes Most field problems trace back to loading, moisture or mixing order rather than to the diluent itself. • Add the diluent to the resin at 25-40 °C under low shear, then blend until uniform before charging filler or hardener. • Keep the drum sealed. The specification caps water at 0.1%, and an open drum in a humid season pulls headspace moisture that shows up later as a hazy film. • Never count YLD-9006 as solvent. It stays in the film and becomes part of the network, so solvent-release calculations do not apply. • Re-check EEW on arrival. Cardanol is a natural feedstock, so EEW shifts between lots and the hardener dose should follow it. • Store in a well-ventilated area, away from flames and direct sunlight, and close the cap tightly after use. • Watch pot life at high loading. More diluent extends pot life, which helps a short line and hurts a fast-cure process. • Measure mix viscosity at line temperature on composites work, because a diluent reading 40 mPa·s at 25 °C behaves differently in a 35 °C bath. 7. Applications of Cardanol Glycidyl Ether YLD-9006 The product page lists five application fields, and each one asks something different from the diluent. Application Role of YLD-9006 Field note High-solids coatings Cuts viscosity so solvent demand falls Watch sag resistance above 20 phr Electronic potting Low mix viscosity for void-free fill Confirm chloride limits with the customer Adhesives Toughening from the C15 chain Check peel strength, not just shear Casting compounds Improves flow around inserts Exotherm rises with batch size Composites, FRP winding Lowers bath viscosity for fibre wet-out Recheck bath viscosity as it ages Composites, pultrusion Improves impregnation of dense reinforcement Balance against green strength Modified curing agents Reactive building block, per the product page Develop in-house, not off the shelf Coatings and potting carry the volume, which is why the product page flags them first. For an epoxy resin coatings project, the diluent is the cheapest lever on volatile organic content, and it works in solvent-borne and solvent-free systems. On epoxy resin adhesives, YLD-9006 does two jobs at once: it thins the mix for better substrate wetting, and it leaves a flexible C15 segment in the cured bond line. Composite work is a different question. In epoxy resin composites, viscosity reduction only helps if it survives the run, so a bath that starts at 400 mPa·s and doubles over four hours ruins the last third of the batch. 8. Frequently Asked Questions What are the CAS number, EEW and viscosity of cardanol glycidyl ether YLD-9006? CAS No. 171263-25-5 belongs to cardanol glycidyl ether YLD-9006, which is published at EEW 355-500 g/eq with viscosity 30-50 mPa·s at 25 °C, with water capped at 0.1% and hydrolyzable chloride at 0.5% maximum. The EEW band is wide because cardanol is a natural feedstock, so plan the hardener dose around the actual lot value. Is YLD-9006 monofunctional or difunctional? It is monofunctional. The product page describes YLD-9006 as a single epoxy-based active diluent, and the EEW of 355-500 g/eq is consistent with one epoxide on a C15 chain. If the formulation needs crosslink density from the diluent, use a difunctional cardanol grade instead. How much YLD-9006 should be added, and does it change hardener dosage? Start at 5 phr and step up in 5 phr increments, with most systems settling between 10 and 20 phr. The hardener dose does change: at 15 phr the blend EEW rises from 170 to about 184 g/eq, and the DMDC requirement falls from 35.3 phr to 32.6 phr. Does YLD-9006 lower the glass transition temperature of the cured resin? Any monofunctional diluent lowers the glass transition temperature, and loading is the lever. The product page reports less impact on the thermal properties of the cured material than fatty-chain monofunctional diluents show, but that advantage shrinks as loading rises. Above 20 phr, expect a measurable drop. Can YLD-9006 replace BGE or C8-10 AGE at a 1:1 ratio? Not by weight. BGE sits at EEW 147-157 g/eq and C8-10 AGE at 220-250 g/eq, while YLD-9006 runs 355-500 g/eq, so an equal-weight swap changes the stoichiometry. Recalculate the hardener, then confirm that the higher mix viscosity still meets the process window. What is the shelf life and storage condition for YLD-9006? Shelf life is at least 12 months from the date of manufacture in the original packing at ambient temperature. Store the drum in a well-ventilated area away from flames and direct sunlight, and close the cap tightly after use; details sit in the MSDS. 9. Packaging, Storage and Safety YLD-9006 ships in drums and holds its specification for at least 12 months in the original packing at ambient temperature. Keep drums in a well-ventilated area, away from flames and direct sunlight, and reseal them tightly after every draw-off. Decant in a bunded area, wear nitrile gloves and eye protection, and follow the exposure limits on the MSDS. No certification should be assumed from this article. Flame-retardant, food-contact and electrical classifications depend on the finished formulation and cure schedule, not on the diluent alone, so test the cured part. Request the TDS, MSDS and COA for the shipping lot, and re-verify EEW, viscosity and water content on arrival.

DOPO modified phenolic epoxy resin is a halogen-free reactive flame-retardant resin in which the DOPO unit is chemically bonded into the epoxy backbone. Yolatech now supplies five solution grades with EEW 280-390 g/eq and 70-75% solids for halogen-free copper clad laminates and electrical laminates.   Product Code: YLDP series — YLDP-315-M75 / YLDP-300-K70 / YLDP-310-EK75 / YLDP-300-K75 / YLDP-60-K75Key Raw Material CAS No.: 35948-25-5 (DOPO)Product Category: DOPO Modified Phenolic Epoxy Resin / Halogen-Free Reactive Flame Retardant Epoxy Resin 1. Product Information Item Information Chemical Description Phenolic epoxy resin modified with DOPO (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide), reacted through the DOPO P-H bond onto the epoxy chain Supplied Grades YLDP-315-M75, YLDP-300-K70, YLDP-310-EK75, YLDP-300-K75, YLDP-60-K75 Key Raw Material CAS No. 35948-25-5 (DOPO) DOPO Molecular Formula C12H9O2P (phosphorus content of the DOPO molecule: approx. 14.3%) Supplied Form Solution-type resin, non-volatile content 70–75±1%, viscosity up to 3000 mPa·s depending on grade Flame Retardant Type Reactive phosphorus-based, halogen-free Family Position One of three DOPO modified phenolic epoxy types from Yolatech, alongside DOPO-HQ modified and DOPO-NQ modified grades Category Halogen-free flame retardant epoxy resin for printed circuit substrates, copper-clad laminates and electrical laminates   2. Product Description DOPO is a rigid cyclic phosphinate whose single P-H bond is what makes it versatile: it adds readily across epoxy groups, double bonds, carbonyls, halogenated sites and amino groups, which is why DOPO has become the standard starting material for reactive phosphorus flame retardancy in electronics. Reacted onto an epoxy backbone, the P-H bond opens the oxirane ring and the phosphorus ends up joined to the polymer through a direct phosphorus–carbon bond. That P–C linkage is the practical difference between a reactive DOPO resin and a phosphorus additive: bonded phosphorus cannot migrate to the surface, cannot be extracted by moisture or solvents, and cannot bloom during lamination. It is also more hydrolytically stable than the P–O–C ester linkages used in many phosphate-based additives, an advantage in laminates that must pass moisture-absorption and CAF testing. In a fire it works two ways at once: condensed-phase char formation insulates the substrate, while gas-phase phosphorus radicals interrupt the combustion chain reaction. No bromine is involved, so no hydrogen bromide is released and smoke density stays lower. Yolatech supplies DOPO modified phenolic epoxy resin as a series of solution-type grades. All five grades are halogen-free flame retardant epoxy resin systems with 70–75% non-volatile content and EEW 280–390 g/eq, sized for varnish preparation and dip-coating lines rather than neat casting. The series shares the property profile the whole family is known for — flame retardancy, heat resistance, low toxicity and low water absorption and expansion coefficient — and sits alongside the DOPO-HQ modified phenolic epoxy resin and DOPO-NQ modified phenolic epoxy resin grades, which carry additional phenolic functionality for higher-Tg requirements.   3. DOPO Modified vs DOPO-HQ vs DOPO-NQ: Choosing the Right Derivative All three family members put phosphorus into the network covalently, but by different chemistry. The base phenolic epoxy resin modified directly with DOPO relies on the P–C bond formed at the oxirane ring; the DOPO-HQ derivative is built on hydroquinone and contributes two phenolic hydroxyl groups; the DOPO-NQ derivative is built on a naphthoquinone core. The table compares the three using grade data published on the respective Yolatech product pages. Comparison Item DOPO Modified (this page) DOPO-HQ Modified DOPO-NQ Modified Phosphorus Bonding Direct P–C bond onto the epoxy chain DOPO-HQ moiety with two phenolic OH groups in the backbone DOPO-NQ moiety on a naphthalene-ring structure Published EEW Range, g/eq 280–390 210–340 300–360 Published N.V. Range, % 70–75 70–80 75 Published Viscosity, mPa·s Up to 3000 (lowest cap in series: <1500) Up to 7000 (lowest cap: <1000) 1000–3000 Distinctive Strength High phosphorus efficiency of the DOPO unit combined with a tight, low-viscosity varnish window Two reactive phenolic sites support higher crosslink density and Tg Naphthalene core supports heat resistance Typical Use Bias Halogen-free copper-clad laminate varnishes and dipping lines High-Tg halogen-free laminates for lead-free assembly Halogen-free laminates where heat resistance is the priority Against a brominated route the comparison is sharper: a brominated epoxy resin or high brominated epoxy resin system typically needs 15–18% bromine in the cured resin to reach UL 94 V-0, while a phosphorus system generally reaches the same rating at approximately 1.5–2.0% phosphorus. That tenfold difference in loading changes the whole formulation balance: less non-structural mass, lower smoke, and no hydrogen bromide.   4. Typical Technical Information The following grade data are the published specification ranges for the DOPO modified phenolic epoxy resin series. Official sales, quotation or technical commitment should be based on company TDS, MSDS, COA or mutually confirmed documents. Grade No. EEW (g/eq) Viscosity (mPa·s) N.V. (%) YLDP-315-M75 295–335 1000–3000 75±1 YLDP-300-K70 280–320 <2000 70±1 YLDP-310-EK75 290–330 <3000 75±1 YLDP-300-K75 280–320 <3000 75±1 YLDP-60-K75 330–390 <1500 70±1   Item Typical Information Flame Retardant Mechanism Reactive phosphorus; condensed-phase char formation combined with gas-phase radical quenching Target P in Cured Laminate Approx. 1.5–2.0% for UL 94 V-0 capability (formulation dependent; confirm the grade phosphorus value from the TDS) Common Curing Systems Dicyandiamide and phenolic novolac cure for laminate prepreg; confirm the curing agent and accelerator package against your own laminate data Storage Store in a well-ventilated area, away from flames and direct sunlight; close the cap tightly immediately after use Shelf Life At least 12 months from the date of manufacture in the original packing at ambient temperatures Safety Documentation All safety information is provided in the Material Safety Data Sheet   5. Formulation Guidance: Grade Selection and Stoichiometry Grade selection in this series is mostly a viscosity-and-solids decision, because the chemistry is shared. Three working rules cover most cases: • For dipping and coating lines that need the lowest viscosity, YLDP-60-K75 (viscosity <1500 mPa·s, EEW 330–390 g/eq) and YLDP-300-K70 (<2000 mPa·s) leave the widest processing window. • For higher build per pass and lower solvent load, the 75% N.V. grades (YLDP-315-M75, YLDP-310-EK75, YLDP-300-K75) deliver more resin per kilogram of varnish than the 70% grades. • For higher crosslink demand, the higher-EEW YLDP-60-K75 shifts the stoichiometry toward more curing agent per 100 parts resin, which raises network density in the cured laminate. Curing agent dosage follows the standard equivalent-weight calculation: phr = AHEW × 100 ÷ EEW Worked example with a mid-series grade at EEW 300 g/eq: against diethylenetriamine (AHEW approx. 20.6 g/eq) the theoretical dosage is 20.6 × 100 ÷ 300 = approx. 6.9 phr. Against dicyandiamide (AHEW approx. 28 g/eq, the workhorse latent cure for copper-clad laminate prepreg) it is 28 × 100 ÷ 300 = approx. 9.3 phr. Compare that with a standard solution-type bisphenol A epoxy resin at EEW 190 g/eq, which needs approx. 14.7 phr of dicyandiamide — the DOPO-modified grade needs less curing agent per unit weight because more of its mass is already resin backbone. Dicyandiamide-cured laminate systems normally run with an accelerator to place the cure window correctly — see the site articles on dicyandiamide epoxy curing agents and on DMP-30 as a curing accelerator. All dosages above are theoretical starting points: verify the actual ratio, gel time and B-stage flow on your own test panels before a production run.   6. Processing Notes • Because the grades are supplied as solutions, varnish preparation is mostly dilution and blending. Add the curing agent only after the resin blend is homogeneous and at the target temperature and solids. • Control varnish temperature during mixing. Viscosity falls with temperature, and a line set up on a cold morning will run differently from the same varnish on a hot afternoon — check viscosity at a fixed reference temperature. • Re-check non-volatile content and viscosity of every incoming batch before use — a fast test that protects the dip-tank from a whole-batch loss. • After any recipe change, re-validate gel time and B-stage flow. Prepreg flow that drifts out of the lamination window is the most common failure mode after a resin-grade switch. • Close container caps tightly immediately after use, and keep drums away from flames and direct sunlight, exactly as the product storage instructions specify.   7. Applications Application Field Function / Description Halogen-Free Flame Retardant Printed Circuit Substrates Reactive phosphorus flame retardancy built into the resin itself, for PCB substrate laminates that must meet halogen-free requirements Electronic Copper-Clad Laminates Varnish-grade resin for CCL impregnation lines; 70–75% N.V. solutions and viscosity caps from <1500 to 3000 mPa·s fit standard dipping and coating equipment Electrical Laminates Insulating laminate sheets and fabricated parts where intrinsic halogen-free flame retardancy, low water absorption and stable expansion coefficient are required The common thread across all three fields: the flame retardant element must survive the whole service life of the board. Because the phosphorus is part of the network, the rating does not depend on an additive that can drift out during lamination, solder reflow or years of thermal cycling. For the wider resin portfolio, the heat resistant epoxy resin family and the multifunctional grades are the usual companions to this series in high-reliability laminate formulations.   8. Frequently Asked Questions What is DOPO modified phenolic epoxy resin? It is a phenolic epoxy resin into which DOPO (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, CAS 35948-25-5) has been reacted through its P-H bond, so the phosphorus becomes a covalent part of the polymer backbone. The result is a halogen-free reactive flame retardant resin, supplied here as five solution grades with EEW 280–390 g/eq and 70–75% non-volatile content, used mainly in halogen-free printed circuit substrates, electronic copper-clad laminates and electrical laminates. How is the base DOPO modified grade different from DOPO-HQ and DOPO-NQ modified grades? The base grade bonds phosphorus directly to the epoxy chain through a P–C bond. DOPO-HQ modified grades add two phenolic hydroxyl groups per DOPO-HQ unit, which supports higher crosslink density and Tg in high-Tg laminates, while DOPO-NQ modified grades carry a naphthalene-ring structure oriented toward heat resistance. In published grade data the base series runs EEW 280–390 g/eq at 70–75% N.V., the DOPO-HQ series runs EEW 210–340 g/eq at 70–80% N.V., and the DOPO-NQ series runs EEW 300–360 g/eq at 75% N.V. Which grade should I start with for a copper-clad laminate varnish? Start from your line's viscosity limit and target solids. For the widest low-viscosity window, YLDP-60-K75 (viscosity <1500 mPa·s, EEW 330–390 g/eq) or YLDP-300-K70 (<2000 mPa·s) are the natural starting points. If you want more resin per pass and less solvent to evaporate, choose one of the 75% N.V. grades: YLDP-315-M75, YLDP-310-EK75 or YLDP-300-K75. Confirm the final selection with a trial batch, because prepreg flow and gel time respond to the whole formulation, not to the resin alone. How do I calculate the curing agent dosage for a DOPO modified epoxy? Use the equivalent-weight ratio: phr = AHEW × 100 ÷ EEW. With a grade at EEW 300 g/eq, dicyandiamide (AHEW approx. 28 g/eq) gives a theoretical dosage of approx. 9.3 phr, and diethylenetriamine (AHEW approx. 20.6 g/eq) gives approx. 6.9 phr. These are theoretical values — confirm the practical dosage on your own system together with the accelerator package and cure schedule. Is DOPO modified phenolic epoxy resin truly halogen-free? Yes. The flame retardant element is phosphorus bonded into the resin backbone, not a brominated compound, so the cured laminate contains no added bromine and produces no hydrogen bromide when heated. The family is designed to support halogen-free requirements for printed circuit substrates as an alternative to halogen-containing flame retardants. Compliance documents for a specific shipment should be requested together with the COA. What is the shelf life and how should the resin be stored? The shelf life is at least 12 months from the date of manufacture when stored in the original packing at ambient temperatures. Store in a well-ventilated area, keep away from flames and direct sunlight, and close the cap tightly immediately after use. All safety information is provided in the Material Safety Data Sheet.   9. Packaging, Storage and Safety Packaging: drum package, in accordance with the company delivery arrangement for the order. Storage: at least 12 months from the date of manufacture in the original packing at ambient temperatures. Store in a well-ventilated area, keep away from flames and direct sunlight, and close the cap tightly immediately after use. Safety: all safety information is provided in the Material Safety Data Sheet. Use protective gloves and safety goggles during handling and refer to the MSDS for detailed requirements.

Yolatech YLDP-320 is a DOPO-HQ modified phenolic epoxy resin with 2.9–3.2% phosphorus chemically bonded in the backbone. It delivers halogen-free UL 94 V-0 flame retardancy in high-Tg PCB laminates, electronic encapsulation and advanced composites, and requires no brominated additives such as TBBPA.   Product Code: YLDP-320Key Raw Material CAS No.: 99208-50-1 (DOPO-HQ)Product Category: DOPO-HQ Modified Phenolic Epoxy Resin / Halogen-Free Reactive Flame Retardant Resin 1. Product Information Item Information Chemical Description Phenolic epoxy resin modified with DOPO-HQ (10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) Product Code / Trade Name YLDP-320 Key Raw Material CAS No. 99208-50-1 (DOPO-HQ) DOPO-HQ Molecular Formula C18H13O3P Appearance Light yellow solid Flame Retardant Type Reactive phosphorus-based, halogen-free Category Halogen-free flame retardant epoxy resin for laminates and encapsulation   2. Product Description Conventional flame retardant epoxy systems for PCB laminates rely on brominated chemistry, most commonly TBBPA. Bromine works, but it brings three persistent problems: it adds mass without contributing to the network, it raises smoke density and toxic gas release during combustion, and it sits under continuous regulatory scrutiny in the European Union. As the electronics industry moves toward halogen-free designs, formulators need a flame retardant that is part of the polymer backbone instead of an additive suspended inside it. DOPO-HQ modified phenolic epoxy resin answers that requirement. The DOPO-HQ moiety is built into the resin chain, so it cannot migrate to the surface, cannot be extracted by moisture, and cannot bloom out during lamination. Phosphorus acts through two simultaneous mechanisms: in the condensed phase it promotes char formation and protects the underlying polymer, and in the gas phase it releases phosphorus-containing radicals that quench the combustion chain reaction. The result is a UL 94 V-0 capable system without a single bromine atom. YLDP-320 is the DOPO-HQ modified phenolic epoxy grade in the Yolatech DOPO-modified phenolic epoxy resin series. It carries 2.9–3.2% phosphorus directly in the molecule, which means a formulator can reach the 1.5–2.0% phosphorus level normally required for UL 94 V-0 in the cured laminate without adding a separate flame retardant package. It also keeps the high crosslink density and thermal stability that phenolic epoxy chemistry is known for — the property that matters most when the board has to survive lead-free soldering.   3. Why DOPO-HQ Instead of TBBPA Both routes can reach UL 94 V-0 in an FR-4 equivalent laminate. They reach it very differently, and the differences show up in smoke, dielectric behaviour, regulatory exposure and mass efficiency. If you currently run a high brominated epoxy resin or a brominated epoxy resin system, the table below maps out exactly where a phosphorus route diverges. Comparison Item DOPO-HQ Modified Phenolic Epoxy (YLDP-320) Flame Retardant Element Phosphorus (halogen-free) Typical Loading for UL 94 V-0 Approx. 1.5–2.0% P in the cured resin (formulation dependent) Comparison — TBBPA System Typically requires 15–18% Br in the cured resin to reach the same rating, i.e. a substantially higher additive load Halogen Content None. Fully halogen-free by design. Smoke and Toxic Gas Lower smoke density and lower toxic gas release; no hydrogen bromide formation Regulatory Position Designed to support RoHS and REACH compliance. TBBPA remains under REACH SVHC evaluation and is restricted in some markets. Migration and Blooming Phosphorus is covalently bonded into the network; no migration, no surface blooming, no moisture extraction Crosslink Density and Tg DOPO-HQ contributes phenolic hydroxyl functionality, helping maintain crosslink density and heat resistance in high-Tg systems The practical implication is mass efficiency. A brominated system needs 15–18% bromine in the cured resin to reach V-0. A phosphorus system reaches the same rating at roughly 1.5–2.0% phosphorus. That difference changes the balance of the entire formulation: less non-structural mass, more room for fillers or for resin chemistry chosen on mechanical and dielectric merit rather than on flame retardancy alone.   4. Typical Technical Information The following data are typical values for YLDP-320. Official sales, quotation or technical commitment should be based on company TDS, MSDS, COA or mutually confirmed documents. Item Typical Information Appearance Light yellow solid EEW, g/eq 300–340 Solid content, wt% MIN 99.0 Softening point, °C 70–85 Phosphorus content, % 2.9–3.2 Flame Retardant Mechanism Reactive phosphorus; condensed-phase char formation combined with gas-phase radical quenching Target P in Cured Laminate Approx. 1.5–2.0% for UL 94 V-0 (formulation dependent) Common Curing Systems DICY, phenolic novolac and anhydride systems. Confirm the curing agent and accelerator package against your own laminate data. Transport Information Non-hazardous solid in normal industrial classification. Refer to the actual MSDS for the applicable classification of your shipment.   5. Formulation Guidance: How Much to Use Because YLDP-320 already contains 2.9–3.2% phosphorus, using it as the main resin normally reaches the target flame retardant level without any additional flame retardant additive. When it is blended with a standard bisphenol A epoxy or a conventional phenolic epoxy resin, the blend phosphorus content is a simple weighted average: P(blend) = w1 × P1 + w2 × P2 + … Worked example: a blend of YLDP-320 (3.0% P) and a standard bisphenol A epoxy (0% P). To reach 1.5% P in the cured resin, the YLDP-320 fraction is 1.5 ÷ 3.0 = 50% by weight. To reach 2.0% P, the fraction is 2.0 ÷ 3.0 = approximately 67%. The example is a calculation guide only — verify the actual flame retardant rating on your own laminate, because resin, curing agent, filler and glass content all shift the result. Two formulation notes worth remembering: • Do not simply maximise the DOPO-HQ resin fraction. Unreacted phosphorus groups act as a plasticiser and can pull down Tg and interlayer adhesion. The target is the lowest phosphorus level that still passes V-0, not the highest. • Nitrogen–phosphorus synergy is real. Combining the phosphorus system with a nitrogen-containing co-agent can improve char quality and let you reduce total phosphorus loading.   6. Processing Notes: Dissolution and Cure YLDP-320 is a solid with a softening point of 70–85 °C and is normally dissolved into the varnish together with the other resin components before the curing agent is added. • Keep the dissolution temperature controlled. High temperature held for too long will consume epoxy groups and start the network before the varnish is applied. • Add the curing agent only after the resin is fully dissolved and the varnish is homogeneous and at the target temperature. • Watch gel time after a recipe change. Increasing the DOPO-HQ fraction changes the reactivity balance, and prepreg flow can fall out of the lamination window if gel time is not re-checked. • Verify each incoming batch with a simple gel time test and a visual clarity check before scaling up. It is a ten-minute test that prevents a production batch loss.   7. Applications Application Field Function / Description Halogen-Free PCB Laminates High-Tg halogen-free FR-4 equivalent laminates for lead-free assembly, servers, communications equipment and automotive electronics Electronic Encapsulation Potting and encapsulation compounds requiring permanent, non-migrating flame retardancy together with electrical insulation High-Performance Composites Halogen-free prepreg and structural composites for aerospace, rail and automotive interiors where smoke and toxicity limits apply Electrical Insulation Dry-type transformer and high-voltage insulation systems needing intrinsic halogen-free flame retardancy that survives long-term thermal ageing Powder Coatings Reactive flame retardant component in epoxy powder coating formulations   8. Frequently Asked Questions What is the phosphorus content of YLDP-320? YLDP-320 contains 2.9–3.2% phosphorus by weight. For comparison, the DOPO-HQ raw material itself contains approximately 9.6% phosphorus. Because YLDP-320 is a resin with the DOPO-HQ structure built into the polymer chain, the phosphorus is available to the cured network as a reactive component rather than as a dispersed additive. Can DOPO-HQ modified epoxy replace TBBPA in an FR-4 laminate? Yes, and it does so with a much lower loading. A brominated system typically needs 15–18% bromine in the cured resin to reach UL 94 V-0, whereas a phosphorus system typically reaches the same rating at approximately 1.5–2.0% phosphorus. The substitution is not a drop-in one-for-one swap: the resin ratio, curing agent, accelerator and gel time all need to be re-balanced and re-validated on your own test panels. What Tg can be expected from a DOPO-HQ laminate? Formulated systems based on DOPO-HQ modified phenolic epoxy are used in high-Tg laminates for lead-free soldering, where the usual requirement is a Tg above 170 °C. The actual value depends on the blend ratio, the curing agent, the filler and the cure schedule, so it must be confirmed against your own formulation. YLDP-320 is solid with a softening point of 70–85 °C, which leaves a practical processing window for varnish preparation. What is the difference between DOPO and DOPO-HQ? DOPO is the base molecule, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, with a single reactive P-H bond and a phosphorus content around 14.3%. DOPO-HQ is the hydroquinone derivative, with two phenolic hydroxyl groups and a phosphorus content around 9.6%, which gives it two reactive sites and improved crosslink density for high-Tg systems. Yolatech also supplies DOPO modified phenolic epoxy resin and DOPO-NQ modified phenolic epoxy resin so that a formulator can select the derivative that matches the target Tg and loading. Is YLDP-320 RoHS and REACH compliant? YLDP-320 is halogen-free and is designed to support RoHS and REACH compliance in the finished article. It contains no TBBPA and no brominated flame retardant. Regulatory status must always be confirmed against the latest official text, and the compliance documents for a specific shipment should be requested with the COA. How should DOPO-HQ epoxy be stored? Keep the product tightly sealed in a cool, dry and well-ventilated place, away from heat, direct sunlight and moisture. DOPO-derived materials are moisture sensitive, so an opened container should be re-sealed promptly. Refer to the MSDS for detailed handling requirements.   9. Packaging, Storage and Safety Packaging: usually available in bags or drums in accordance with supplier specifications. Actual packaging should follow the company delivery arrangement for the order. Storage: keep tightly sealed in a cool, dry and well-ventilated place. Avoid heat, direct sunlight and moisture ingress. Keep away from strong oxidizing agents, strong acids and incompatible materials. Safety: use protective gloves, safety goggles and protective clothing during handling. Avoid inhalation of dust. Refer to the MSDS for detailed safety information.

Two decisions settle most of the outcome in a DDS-cured epoxy: how much hardener goes into the mix, and how the part is heated. Both are calculable before the first trial. In practice, both are often set by habit — a ratio copied from an old formulation sheet, or an oven profile carried over from a different hardener.   DDS dosage is not a number to copy. It is a number to calculate from equivalents, and then adjust on purpose.   4,4'-Diaminodiphenyl sulfone carries four active amine hydrogens on a molar mass of 248.30 g/mol. That gives an amine hydrogen equivalent weight (AHEW) of approximately 62.1 g/eq. Combined with the epoxy equivalent weight (EEW) of your resin, that single constant fixes the stoichiometric dosage. Everything after it — running above or below stoichiometry, adding an accelerator, extending the post-cure — is a deliberate adjustment with a measurable consequence.   From equivalents to grams The calculation is the same one used for every amine hardener: phr = (AHEW ÷ EEW) × 100 phr = parts of hardener per 100 parts of resin, by weight   For a standard liquid DGEBA at 185–190 g/eq — the workhorse laminating resin — this lands at about 33 phr. Published application data for 4,4'-DDS in DGEBA reports 33.4 phr, which is the same figure reached from the other direction.   Resin system Typical EEW (g/eq) Stoichiometric 4,4'-DDS Note Standard liquid DGEBA 185–190 ≈33 phr Matches the 33.4 phr reported in DGEBA/DDS application literature DGEBA / DGEBF blend 170–180 35–37 phr Lower EEW raises the hardener demand Novolac-modified laminate resin 175–200 31–35 phr Calculate on the blend, not on the base resin TGMDA-based aerospace matrix 165–175 effective 35–38 phr TGMDA alone is 111–125 g/eq; the blend is what counts Aminophenol-type multifunctional epoxy 95–110 56–65 phr High functionality means a high hardener demand Stoichiometric values calculated from AHEW 62.1 g/eq. Always confirm against the EEW on the current resin lot certificate.   Figure 1. Stoichiometric 4,4'-DDS dosage as a function of epoxy equivalent weight, calculated from AHEW 62.1 g/eq. Original chart.   The case that trips people up: TGMDA TGMDA — tetraglycidyl methylenedianiline, also written TGDDM and sold as MY-720 or MY-721 — has an EEW of roughly 111–125 g/eq. Read on its own, that suggests a DDS requirement near 50 phr. Aerospace prepreg matrices are not built that way, and the reason is worth understanding.   A widely cited high-performance matrix composition contains four epoxy components and two cure components. The epoxy blend totals 74.0 parts against 25.0 parts of 4,4'-DDS — about 34 phr. Worked back through equivalents, that is roughly 93% of stoichiometry for the blend.   Component wt% Role TGMDA (TGDDM) 56.5 Tetrafunctional base resin; supplies the high crosslink density Alicyclic diepoxy carboxylate 9.0 Viscosity and toughness modifier Epoxy cresol novolac 8.5 Reactivity and heat resistance 4,4'-DDS 25.0 Hardener; ≈34 phr on 74.0 parts of epoxy Boron trifluoride amine complex 1.1 Accelerator Composition as reported for a standard high-performance epoxy matrix system. Percentages are literature values, not a YolaTech formulation.   The lesson is not the number 34. It is that DDS is dosed against the whole epoxy blend, not against the headline resin on the front of the drum.   Running off stoichiometry, on purpose Most production formulations do not sit at a stoichiometric index of 100. A typical working band is 90–105. Moving within that band is a way of trading properties, and it is worth being explicit about the trade.   Running epoxy-rich — index below 100 — generally raises Tg and lowers moisture uptake, because the excess epoxy is consumed in secondary reactions rather than left as unreacted amine. The cost is toughness. Running amine-rich can improve toughness and adhesion, but any amine that stays unreacted acts as a plasticiser inside the network and pulls Tg down. Neither direction is universally correct; both are measurable.   The companion article on this blog looks at a published TGPAP/BPF study where eleven design runs varied blend composition and the amine-to-epoxy ratio. A longer processing window did not automatically produce a higher Tg, and the optimised case settled at 181.2 ± 0.8 °C with a stoichiometric ratio of 0.60. That is a useful reminder that DDS performance belongs to the complete formulation, not to the hardener name.   The cure schedule is a ramp, not a temperature DDS is a latent hardener rather than a fast one. The sulfone bridge withdraws electron density from both amine nitrogens, so reaction onset sits well above room temperature. The practical consequence is useful: the hardener stays effectively inert while the resin is mixed, impregnated or cast, and heat is what starts the cure.   That latency is also why the cure schedule cannot be reduced to one number. Published schedules for DDS systems look like this.   System DDS level Cure schedule DGEBA 30 phr Isothermal at 180 °C DGEBF stoichiometric Ramp from 35 °C to 180 °C at varied rates; hold 3 h at 180 °C TGDDM with mixed DDS isomers 33 phr total 150 °C 2 h → 180 °C 1 h → 210 °C 2 h TMBPBT epoxy 41 phr Varied cure temperatures and times Two-stage industrial practice calculated 130 °C 2 h → 200 °C 2 h Schedules as reported in DDS application literature and supplier application guidance.   Two patterns are worth noting. First, every schedule finishes high — between 180 and 210 °C — because that is where conversion and Tg are won. Second, the staged ramp exists for a physical reason rather than a traditional one. A thick section driven straight to the final temperature can concentrate the exotherm, which shows up as voids and internal stress. Staging lets the gel point arrive before the exotherm peak.   If the final temperature is a hard process limit, an accelerator is the standard route rather than a longer dwell at a lower temperature. BF3-monoethylamine appears at 1.1 phr in the matrix formulation above. Supplier guidance for DDS also describes adding roughly 0.5–1.2% of an acidic accelerator to bring the cure down to about 100 °C for one hour — but the DDS level has to be recalculated when a catalyst is carrying part of the reaction.   What Tg to expect DSC data for DDS-cured epoxy is commonly reported in the 180–210 °C band, against roughly 150–170 °C for an aromatic amine such as m-phenylenediamine in a comparable system. Decomposition onset (Td5%) sits near 363 °C. Optimised matrices in the formulation literature report DDS systems above 250 °C.   Those are system-level values, not constants of the molecule. Resin choice, stoichiometric index, cure schedule and post-cure all move the result. A Tg quoted without the resin and the cure schedule behind it is not a specification; it is a claim.   Where the powder goes matters as much as how much Dosage is only half the job. DDS melts at 175–181 °C, which is above the temperature at which most formulations are mixed. The hardener therefore enters the resin as a solid, and how that solid is distributed decides whether the cured part is uniform.   Three routes are in common use. Powder dispersion. Fine DDS is dispersed in the liquid resin at 80–100 °C and dissolves progressively as the mix heats. The simplest route, and the most dependent on particle size distribution and mixing energy. Solution. DDS is dissolved in hot solvent, or introduced as part of a solvent-borne varnish. The best uniformity, at the cost of a drying step and the solvent question that comes with it. Melt blending. Short residence at 150–170 °C. Fast and uniform, but it consumes the processing time that DDS latency would otherwise give you.   The failure mode to watch for is agglomeration. Clusters of undissolved DDS create hardener-rich and hardener-poor zones at the same time. The hardener-poor zones stay under-cured, and the symptom is deceptive: the part passes a room-temperature test, then shows a low Tg, or a soft core in a thick section, or a scatter of results that cannot be reproduced. Optical microscopy on a cured cross-section is the cheapest way to catch it before it reaches a customer.   Reading an unexpected result When a DDS formulation does not behave, the symptom usually points at one of six causes.   What you observe Most likely cause What to check first Tg below the design target Incomplete conversion Residual exotherm by DSC; extend or raise the post-cure Soft or tacky core in a thick section Agglomerated hardener Cross-section under optical microscopy; particle size distribution Voids or cracking during cure Exotherm concentrated by a direct ramp Ramp rate, section thickness, filler level Powder has turned pink or red Surface oxidation in storage Melting point and assay. A slight tint is cosmetic; deep red or caking is not Same formula, different result between lots Dosage copied instead of calculated EEW on the current resin lot certificate; the phr actually weighed One-part mix gels in storage Accelerator level or storage temperature Storage temperature; accelerator loading; dispersion method   Keep a process log, not just a result What makes a DDS trial reusable is the record behind it. A minimum log for one trial: • Resin identity, current-lot EEW, and the phr actually weighed out • Mixing route, mixing temperature, and how long the DDS was in the resin before use • Processing window observed, and the method used to judge it • Cure and post-cure as actually run, not as planned • Tg by DSC or DMA, with the heating rate stated • The ageing test that matters for the application — heat, moisture, chemical or thermal cycling   A trial without that log produces a result nobody can repeat, including the person who ran it.   YolaTech 4,4'-DDS at a glance   Property TDS value Appearance White crystal powder Purity ≥99.0% Melting point 175–181 °C Loss on drying ≤0.30% CAS number 80-08-0 Theoretical AHEW ≈62.1 g/eq, calculated Primary industrial use High-temperature epoxy curing agent Additional TDS use Material for polysulfone amide and other polymers Storage Cool, dry place; avoid direct sunlight Storage life 12 months in the original sealed container at ambient temperature Packaging 25 kg fiber drum   The formulation is the answer, not the molecule 4,4'-DDS sets a high ceiling. The molecule supplies the rigid aromatic network that makes 180–210 °C service possible. How much of that ceiling a part actually reaches is decided by four things that are all under the formulator's control: the dosage calculated from equivalents, the uniformity of the dispersion, the shape of the cure ramp, and whether a post-cure was run to completion.   If the question is what the molecule does, the companion article on this blog covers the mechanism and the application map. If the question is what to weigh and how to heat it, this is the part that decides the outcome.   Send us the resin type, the EEW on the current lot, the process temperature limit and the section thickness. We will work the dosage and the cure schedule through with you — and tell you when DDS is not the right hardener for the job.