Abstract: In this paper, bisphenol A epoxy resin with methyl nadic acid anhydride curing agent was added to DCPD monomer/Grubbs 2nd catalyst, blend polymer was obtained by step reaction polymerization. Contact angle meter, differential scanning calorimeter (DSC), infrared spectrometer (FT-IR), mechanical testing machine and scanning electron microscope (SEM) were used to characterize the epoxy resin-modified PDCPD. The results show that the wettability between modified DCPD monomer and the carbon fiber fabric is significantly improved as the contact angle decreased from 83.2° to 22.6°, and the glass transition temperature of 10 phr epoxy-modified PDCPD is increased from 124.7 ℃ to 133.2 ℃. No epoxy functional group (913 cm^-1) is found in the infrared spectrum of the modified PDCPD, indicating that the epoxy resin in the mixed system reacts completely. The mechanical test shows that the flexural strength of PDCPD after modification is increased by 13.3%, and the fracture toughness is decreased by 11.0%. The microstructure shows that the cured epoxy resin is uniformly distributed inside the PDCPD as microspheres with a diameter of less than 2 μm. The interlaminar shear strength of the carbon fiber composite based on PDCPD after modification is increased from 8.2 MPa to 15.1 MPa, the cross-sectional structure shows that the addition of epoxy resin can effectively improve the adhesion of PDCPD to carbon fibers.

Key words: polydicyclopentadiene, epoxy resin, blending modification, carbon fiber reinforced polymer, interface bonding