Plasma polymerized film of vinyltriethoxysilane as adhesion interlayer between glass fiber and polyester resin

Plasma polymerized vinyltriethoxysilane (pp-VTEO) thin films were deposited on the surface of glass slides, Si-wafers, and glass fibers. Chemical composition of the polymers on flat substrates was examined by Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS), the surface morphology was studied by Atomic force microscopy (AFM), and surface properties were evaluated by the measurement of surface energy. Adhesion between the pp-VTEO film and the glass slide was tested using fully PC-controlled scratch tester with Rockwell ball or diamond tip, fiber-matrix adhesion was assessed using a modified fiber pull-out test, microdroplet technique. Fiber-polyester resin adhesion was characterized in terms of the interfacial shear strength and the dependence of the droplet size was observed. Untreated fibers were tested to serve as controls.