One-pot in situ polymerization of graphene oxide nanosheets and poly(p-phenylenebenzobisoxazole) with enhanced mechanical and thermal properties

Abstract Graphene with unique nanostructures possess fascinating properties which has inspired extensive research on the incorporation of graphene into polymer matrix to improve the properties. So, in this report, we take a facile and effective approach, one-pot in situ polymerization, to prepare graphene oxide (GO)/Poly(p-phenylene benzobisoxazole) (PBO) composite fibers. The GO sheets were first modified by 4, 6-diaminoresorcinol (DAR) a PBO monomer, another monomer terephthalic acid (TPA) were then added for further polymerization. The NH2-functionalized GO (DAR-GO) sheets are an excellent initial platform for molecular chains grafting. It promote the dispersion of GO sheets in PBO matrix and form strong interaction with the PBO molecular chains to enhance load transfer. The tensile module and tensile strength of the PBO-DAR-GO composite fibers containing 1.0 wt% DAR-GO are increased by 35.9% and 19.6%, respectively compared with neat PBO fibers. In addition, the thermal stability of composite fibers also enhanced with DAR-GO content increasing. This approach supplies a novel strategy for preparing ultra-strong properties PBO composite fibers.