Photoinduced cationic frontal polymerization of epoxy–carbon fibre composites

UV-activated frontal polymerization was exploited for the preparation of epoxy–carbon fibre composites. The curing process was investigated showing the frontal behaviour, and the final properties of UV-cured composites were compared with those of the same composites obtained by thermal curing in the presence of amine as hardener. The best curing formulations were designed, defining the photoinitiator-to-thermal initiator ratio, which was 1.5:1.5. It was observed that the presence of the carbon fibres induced an acceleration of the front velocity. By comparing the thermomechanical properties of the thermally cured composite and the same composite crosslinked using the frontal process, we could observe that the latter showed higher Tg value and lower σf. This was attributed to the formation of a different polymeric network structure.