Surface characterization of trimethoxysilane-containing high-solid hydroxyl acrylic resin films

Abstract

In recent years, organosilane-containing copolymers have attracted much attention in antifouling coatings, automotive coatings, fiber, composite materials, biomedical materials, and latex and protection coatings against corrosion owing to their excellent weathering and low surface energy. Trimethoxysilane-containing high-solid hydroxyl acrylic resin used for automotive coatings was prepared by in situ free radical polymerization. The surfaces of the resin film were characterized by solid surface energy, atomic force microscopy and X-ray photoelectron spectroscopy (XPS) measurements. With the increase in silicone content from 0 to 2.5 wt.%, the surface energy of trimethoxysilane-containing hydroxyl acrylic copolymer films decreased from 49 to 40 mN/N and the surface roughness (Rms) on the surface of thin films increased from 0.427 to 0.887 Å. The XPS result indicated that the surface accumulation phenomena of silicone occurred in the surface of the thin films. The phenomena can explain the reason why the incorporation of trimethoxysilane (MPS) into acrylic copolymer by in situ polymerization can decrease its surface energy and increase its outdoor weathering.