MECHANICAL PERFORMANCE OF KEVLAR FABRIC/CARBON NANOFIBER MODIFIED EPOXY COMPOSITES MADE VIA VACUUM ASSISTED RESIN TRANSFER MOLDING

摘要

Kevlar fiber reinforced polymer composites exhibit excellent strength, very low-weight, high stiffness, thermal stability and excellent energy absorption. However, due largely in part to the chemical inertness of crystalline Kevlar fibers, the real potential for this class of reinforcements has not yet been realized. Many other methods have been reported to successfully increase the interfacial strength of Kevlar fiber reinforced polymer (FRP) composites. In this work we use graphitic carbon nano-fibers (CNFs, pristine and oxidized) that are first pre-treated in a reactive diluent and then added to an epoxy resin. The vacuum assisted resin transfer molding (VARTM) method was used to fabricate the composites. Excellent improvements were found for flexural strength, flexural modulus and inter-laminar shear strength (ILSS) for all Kevlar composites made with the CNF modified epoxies as compared to Kevlar/Neat epoxy composites. Composite samples containing nano-modified epoxy with 0.5wt% pre-treated pristine-CNF showed remarkable improvements of 41% for flexural strength, 118% for flexural modulus and 29% improvement for ILSS.