Rapid curing epoxy resin and the properties of carbon fiber/epoxy composite

A rapid curing resin system made from diglycidyl ether of bisphenol A (DGEBA) epoxy, modified imidazole (MIM) and modified aliphatic amine (MAA) was developed. The curing behavior and rheological characteristic of the resin were evaluated by DSC and rheological analysis respectively. The optimum ratio of the blending of curing agents was selected. The carbon fiber/epoxy resin composite laminates using this resin system were manufactured through vacuum assisted resin injection molding (VARIM) under short-term curing schedule. The processing quality and mechanical properties of the laminates were studied and compared with the properties of the laminates under traditional curing schedule. The results show that the curing time of the resin system is 5 min with 95% curing degree, and the cure time of the laminates using the studied resin can be controlled within 13 min under 120 ℃ with more than 95% curing degree and few defects. Compared with the laminates cured in traditional curing schedule (curing time more than 2 h), the laminates manufactured under short-term curing schedule exhibits slight decreases in the flexural property and thermal stability.