Functional polycarbonates for improved adhesion to carbon fibre

In order to improve the fibre-matrix interaction in carbon fibre reinforced composites the polycarbonate (PC) matrix polymer was modified by the introduction of ethyl-3,5-dihydroxybenzoate as reactive sequences in the polycarbonate backbone. This promising strategy can be considered as an alternative approach to the modification of the carbon fibre surface to control and tailor the adhesion between carbon fibres and polymer matrix. The modification of the polycarbonate demonstrated improved adhesion to carbon fibre in pressed films, which was observed with microscopy-ATR-FTIR and SEM when compared to unmodified polycarbonate. Single fibre pull-out testing subsequently confirmed the improved adhesion, demonstrating higher interfacial shear strenght for the functionalized polycarbonate.