5‐aminobenzimidazole@graphene oxide nanosheets doped polyimide nanocomposites: Low‐temperature curing and improved mechanical properties

Abstract

The preparation of polyimide matrix composites with low curing temperature and high mechanical properties is of great importance. In this study, a low‐cost and multi‐functional nanofiller, 5‐aminobenzimidazole grafted graphene oxide (5‐ABZ@GO) has been designed. By nucleophilic attack on 5‐aminobenzimidazole basic groups and doping of GO, the above requirements of polyimide composites were skillfully realized. The results show that when the addition of 5‐ABZ@GO is 1%, the 5‐ABZ@GO/PI nanocomposites can achieve complete imidized at 200°C. Moreover, the nanocomposite prepared by imidization at 200°C has good mechanical and thermal properties (tensile strength is 141.64 MPa, modulus is 6.05 GPa, T5% is as high as 543.5°C), which is better than the PI composites prepared at 320°C. This study provides an innovative approach to preparing polyimide composites that meet mechanical performance requirements while utilizing comparatively lower curing temperatures, low curing temperature polyimide resins provide a new path for integrated composites with structure–function integration.