STUDIES ON THE MODIFICATION OF INTERPHASE INTERFACES BY USE OF PLASMAIN CERTAIN POLYMER COMPOSITE SYSTEMS/

Calcium carbonate and carbon fiber surfaces were modified by use of a series of plasma polymers at different selected plasma conditions, and the effect of surface modification, mainly on the mechanical properti es of composite systems prepared, was investigated. The matrices for t he composite systems employed were polypropylene and epoxy, for the ch alk and C fiber, respectively. Mechanical and thermal studies and scan ning electron microscopy (SEM) pictures revealed that inclusion surfac es, being independent of their geometry and size, can be modified effe ctively by plasma. A polypropylene matrix with 30% modified chalk had better properties than composites with 10% unmodified chalk. Tensile s trength and stress to failure values for single carbon fibers were fou nd to be improved by plasma treatment. Surface-treated carbon fibers y ielded at composites with better interlaminar shear strength and flexu ral strengths.