Abstract
Alkoxysilane‐modified high solids hydroxyl acrylic polyurethane was prepared by solution polymerization. Its structure, surface, and thermal properties were investigated by ^1^H NMR, device of contact angle, thermo gravimetric analysis (TGA), atomic force microscopy (AFM), and X‐ray photoelectron spectroscopy (XPS). Research showed that alkoxysilane modified high solids hydroxyl acrylic polyurethane has superior properties that can be used for automotive paints. The contents of silicone in the alkoxysilane‐modified high solids hydroxyl acrylic polyurethane were 1.25, 1.5, 2, and 2.5 wt %. In this study, γ‐methacryloxypropyltrimethoxysilane (MPTS) was chosen as the modifier. Results showed that the contact angles of water and surface roughness on the film of MPTS modified high solids hydroxyl acrylic polyurethane increased, and thermal stability of the film at high temperatures improved with the increasing of the silicone content in the resins. MPTS modified high solids hydroxyl acrylic polyurethane with 2.5 wt % silicone content had better water resistance, better acid resistance, higher hardness, and excellent weatherability. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1866–1871, 2006