Tertiary-amine-terminated polybutadiene and butadiene acrylonitrile: Synthesis and application in the modification of epoxy resins

Two tertiary-amine-terminated liquid rubbers (TATPB and TATBN) containing polybutadiene and butadiene acrylonitrile are successfully synthesized and used in the modification of epoxy networks. By taking advantage of the flexibility of rubbers, the toughness of epoxy resin has been significantly improved. The addition of 60 phr TATPB and TATBN increased the impact strength of epoxy resins from 12.2 to 59.8 and 92.0 KJ/m 2 , respectively. Meanwhile, due to the dual role of tertiary amine of TATPB and TATBN in catalysis and curing for epoxies, their T g values shifted from 87.7 to 102.0 and 95.7°C, respectively. TATPB with a smaller polarity improves the toughness of the epoxy resin slightly less than TATBN with a larger polarity, but the former is more effective in increasing the T g values. This study demonstrates a novel strategy to enhance the toughness of epoxy composites as well as improve the high temperature resistance by designing the end-structure of toughening agents.