Research on Using Carboxyl-terminated Butadiene-acrylonitrile Rubber to Modify Epoxy Resin

The carboxyl-terminated butadiene-acrylonitrile rubber(CTBN)was used as the toughening modifier of epoxy resin(EP)to synthetize the blendsor prepolymers of CTBN-EP.The structure and characterization of the blends and prepolymers were analyzed by infrared spectroscopy(FT-IR).At the same time,the effect of CTBN content on the mechanical properties of epoxy resin was studied,and the effect of toughening was evaluated.The result of FT-IR showed that there was no chemical reaction occurred during the blending process.During the prepolymerization,the epoxy ring-opening in EP was esterified with the carboxyl group at the active site of CTBN to form ester bond.The effect of CTBN content on the mechanical properties of the system was studied.The results show that the tensile strength of the blends and prepolymers decreases with the increase of CTBN content,the elongation at break increases first and then decreases,and the impact strength increases gradually,which indicates that CTBN has the toughening effect on EP.