Effects of the Reinforcement of Block Copolymer-treated Carbon Fibers on Tensile Properties of Polypropylene Composites

Abstract

Poly(dimethylaminoethyl methacrylate)-block-poly(methyl methacrylate) (PDMAEMA-b-PIAMA) copolymer (BCP) was synthesized as a amphiphilic compatibilizer via reversible-addition fragmentation chain transfer polymerization to improve the interfacial adhesion and compatibility between epoxy sizing of carbon fiber (CF) surface and polypropylene (PP) matrix. The pristine CF (p-CF)/PP and compatibilizer-treated CF (BCP-CF)/PP composites were fabricated using melt mixing and their tensile properties were analyzed. It was confirmed that the CF surface was functionalized with BCP by reaction of tertiary amine in BCP with epoxide group on CF surface through XPS, TGA and FESEM. The tensile strength and modulus of BCP-CF/PP composites were improved by 37.8% and 18.7%, compared to p-CF/PP composites, which could be attributed to the higher interfacial adhesion between CF and PP and thus improved load transfer capability. The enhanced interface adhesion and compatibility of BCP-CF and PP was also examined by morphology observation.