Application of Plasma Polymerization Technique to Improve Interfacial Properties of Glass Fiber/epoxy Composites

In this study, plasma polymerization technique was used to modify the surface of glass fiber under various plasma powers (30, 60 and 90 W) for exposure time of 15 min to improve the compatibility between glass fiber and epoxy matrix. γ -glycidoxypropyltrimethoxysilane (γ-GPS) monomer were used for surface coating of glass fiber. Interfacial properties of composites were investigated by short beam shear test. Surface characterisation of plasma polymerized glass fiber was carried out by means of X-ray photoelectron spectroscopy (XPS). The organic/inorganic character of plasma polymerized γ-GPS (pp-GPS) glass fibers may be demonstrated by the C/Si ratio, which were obtained to be 3.7, 2.7 and 3.9 for 30, 60 and 90 W respectively. In other words, the organic character of ppGPS glass fibers was highest at a plasma power of 90 W. From short beam shear test it has been reached that as the plasma power was increased from 30 to 90 W, interlaminar shear strength (ILSS) values increased. This indicates that the higher plasma powers exhibit the greater interfacial adhesion between glass fiber and epoxy matrix in the studied plasma power range.