In-situ modification of carbon fibers with hyperbranched polyglycerol via anionic ring-opening polymerization for use in high-performance composites

In this study, hyperbranched polyglycerol (HPG) is chemically bound onto carbon fiber (CF) surface by anionic ring-opening polymerization for linking fiber and matrix to release interior and exterior applied forces. To explore the optimal conditions for the successful hyperbranched polymerization of glycidol on the carbon fiber, various characterization techniques were employed. The atomic force microscope quantitative nanomechanical mapping results reveal that the HPG can significantly improve interfacial status between carbon fiber and epoxy matrix. Compared with the mechanical properties of desized fiber based composites, both interfacial shear strength and interlaminar shear strength of HPG grafted fiber/epoxy composites increase by 90.69% and 49.83%, respectively. The adjustable size of HPG grafted on CF endorse the CF modification strategy with the unique characteristic, which can design the optimized interface between CF and resin to meet various scientific and technical demands.