Enhancing the Interfacial Properties of Polyethylene-Based Carbon Fiber Composites Through Low-Temperature Thermally Reduced Graphene

Carbon fiber reinforced polyolefin (CFRPO) composites have been widely applied in many engineering fields owing to their high specific strength and stiffness. However, carbon fiber (CF) with a chemically inert surface and low surface energy results in the weak interfacial interaction and mechanical properties of CFRPO composites. In this work, thermally reduced graphene was coated on CF with poly(diallyldimethylammonium chloride) (PDDA) as a modifier and coupling agent to improve the interfacial strength between CF and the matrix. After incorporated in linear low-density polyethylene (LLDPE) by melt compounding, the yield strength, yield modulus and thermal conductivity of modified CF reinforced polyethylene (LLDPE/CF-PLG) composite were increased by 18.18%, 16.48% and 5.27%, respectively, and the volume resistivity was decreased by 35.32% compared with LLDPE/CF at 30 wt.% content. The characterization results demonstrate that the enhancement of mechanical properties is attributed to the increased specific surface area, surface roughness and oxygen-containing functional groups on the surface of CF-PLG. This strategy provides a new approach for the enhancement of CF reinforced polymer composites.