Abrasion-resistant coatings for plastic and soft metallic substrates by sol-gel reactions of a triethoxysilylated diethylenetriamine and tetramethoxysilane

Inorganic-organic hybrid materials have been prepared by sol-gel reactions of a metal or semi-metal alkoxide along with a silane-modified organic compound or polymer. Mixtures of a triethoxysilylated diethylenetriamine (f-DETA) and tetramethoxysilane (TMOS) were hydrolyzed in an acidic medium, and the resulting hydrolysates were spin- or dip-coated onto polymeric substrates or metallic substrates and then thermally cured into transparent abrasion-resistant coatings. The influences of the pH, concentrations of water and TMOS. pre-hydrolysis time and curing temperature on the abrasion resistance and hardness of the resulting coatings were studied. These hybrid coatings were applied on substrates of bisphenol-A polycarbonate (bis-A PC), APEC HT9353((R)), copper, brass and stainless steel, and the coated substrates exhibited much lower wear rates than the corresponding uncoated ones in standard abrasion tests. (C) 2000 Elsevier Science S.A. All rights reserved.