Diaminodiphenyl sulfone high-temperature resistant epoxy resin curing agent DDS

4,4'-Diaminodiphenyl sulfone (DDS)

●Product Description: Also known as 4,4'-sulfonyldianiline, dapsone, or bis(4-aminophenyl) sulfone, abbreviated as DDS, with a molecular weight of 248.30. It appears as a white or light yellow crystalline powder that oxidizes and turns pink when exposed to air or light. Relative density is 1.33. Melting point ranges from 175 to 181°C. It exhibits high thermal stability in air, beginning to decompose slowly at 280°C. Soluble in organic solvents, almost insoluble in water.

●Structural Formula:

● Technical Specifications:

●Properties: Low viscosity, high heat resistance, excellent chemical resistance. The cured resin demonstrates outstanding heat resistance, anti-yellowing properties, and chemical stability.

●Applications: Used as a high-temperature curing agent for epoxy resin adhesives. However, it has high moisture absorption, poor wet heat resistance, and results in brittle cured products. Recommended dosage is 25-35 parts. It has low reactivity, with a pot life of 1 year for 100g of epoxy resin compound and 3 hours at 100°C. Curing conditions are 130°C/2h + 200°C/2h or 125°C/2h + 200°C/2h. The heat deflection temperature of the cured product is 175-181°C. DDS significantly contributes to the shear strength and heat resistance of epoxy adhesives. To accelerate curing, 0.5%-1.2% of an acidic accelerator, such as a monoethylamine complex, can be added, reducing curing time to 1 hour at 100°C, with DDS dosage lower than the calculated amount. Without an accelerator, DDS dosage should be 10% higher than calculated for optimal cured product performance. Post-treatment can improve the reaction degree, and using 33 parts yields better properties.