THERMOPLASTIC COMPOSITES

PLASMA TREATMENT OF POLYARAMID FILAMENTS WITH AMINES TO INDUCE SURFACE CHEMISTRY MODIFICATION HAS CREATED IMPROVED PERFORMANCE KEVLAR/EPOXY COMPOSITES. PERFORMANCE IMPROVEMENT HAS BEEN ATTRIBUTED TO THE DEVELOPMENT OF COVALENT BONDS, BUT LIMITED DATA SUGGESTS THAT THE SURFACE ENERGETICS COMPATIBILITY BETWEEN THE TWO CONSTITUENTS WAS ALSO ENHANCED. THIS WOULD HAVE ENHANCED INTERFACIAL ADHESION BY IMPROVING SECONDARY BONDING MECHANISMS. THE CURRENT APPROACH TO MEASURING SURFACE ENERGETICS IS INADEQUATE TO RESOLVE THIS ISSUE. SINCE THERMOPLASTICS DO NOT UNDERGO EXCHANGE REACTIONS, IMPROVED INTERFACIAL ADHESION WILL BE DEPENDENT UPON IMPROVEMENTS IN SURFACE ENERGETICS COMPATIBILITY. SURFACE CHEMISTRY MODIFICATION THROUGH PLASMA TREATMENT HAS THE POTENTIAL TO TAILOR THE SURFACE ENERGETICS OF REINFORCING FIBERS TO SURFACE ENERGY CHARACTERISTICS OF THERMOPLASTIC RESINS. TO EXPLOIT THIS POTENTIAL, AN IMPROVED METHOD OF DETERMINING SURFACE ENERGY COMPONENTS IS REQUIRED. THE WILHEMY TECHNIQUE WILL BE APPLIED TO FIBER AND RESIN SURFACE ENERGY MEASUREMENTS, EMPLOYING AN EXPANDED SUITE OF PROBE LIQUIDS, DIVIDED INTO THREE SURFACE ENERGY CLSSIFICATIONS. RESOLUTION OF SURFACE ENERGY COMPONENTS WILL BE OBTAINED. FORMULATION OF PLASMA TREATMENTS TO ACHIEVE IMPROVED SURFACE ENERGETICS COMPATIBILITY BETWEEN FIBERS AND RESINS WILL BE DEVELOPED.