Polydimethylsiloxane containing isocyanate group-modified epoxy resin: Curing, characterization, and properties

• Published in: Journal of applied polymer science Vol. 73; no. 13; pp. 2739 - 2747
• Main Authors: Shih, Wen-Chang, Ma, Chen-Chi M., Yang, Jen-Chang, Chen, Hung-De
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 23.09.1999; Wiley
• Subjects: Applied sciences; Chemical properties; epoxy resin; Exact sciences and technology; isocyanate group; polydimethylsiloxane; Polymer industry, paints, wood; Properties and testing; Technology of polymers; Dimethylsiloxane polymer; Organic isocyanate; Polymer blends; End group; Epoxy resin; Mechanical properties; Experimental study; Thermal stability; Diamine; Internal stress; Curing(plastics); Concentration effect; Moisture regain; Kinetics; Functional group; Modified material
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/(SICI)1097-4628(19990923)73:13<2739::AID-APP22>3.0.CO;2-F

A synthesized polydimethylsiloxane containing an isocyanate group was used to improve the flexibility and to reduce the internal stress of epoxy resin cured with MDA (4,4′‐methylene dianiline). The effect of polysiloxane content on the curing kinetics of a novolac‐type epoxy modified with an isocyanate group was investigated. It was found that the modified epoxy resin showed significant improvement in impact strength. The polysiloxane containing isocyanate groups effectively depressed the internal stress of cured epoxy resins by reducing the flexural modulus and the coefficient of thermal expansion, while the glass transition temperature was increased. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2739–2747, 1999