The novel use of organo alkoxy silane for the synthesis of organic-inorganic hybrid coatings

UV-curable, organic-morganic hybrid coatings based on a UV-curable epoxyacrylate resin (EA) and methacryloxypropyl trimethoxysilane were prepared by the sol-gel method. 2,2'-Bis(4-beta-hydroxy ethoxy) phenyl propane was modified by a coupling agent, 3-isocyanato propyl triethoxy silane, to improve the compatibility of the organic and inorganic phases. The formulations were applied onto Aluminum panels and cured by UV light to obtain a hard and clear coating with a good adhesion. The structural characterization of cured hybrid materials was performed using solid state Si-29 NMR spectroscopy. The real time infrared technique was used to follow the degree of double bond conversion and photopolymerization rate. The thermal properties of the coatings are improved depends on the 'component A' composition in hybrid mixture which was composed of methacryloxy propyl trimethoxysilane (MAPTMS) and trimethoxysilane terminated HEPA urethane (TMSHU). The char yield of pure epoxy acrylate resin was 0.7 wt% and that of 30 wt% of component A containing hybrid coating was 4.6 wt% at 900 degrees C in air atmosphere. The morphology of the hybrid materials was examined by scanning electron microscopy. The hybrids were nanocomposites. (c) 2006 Elsevier B.V. All rights reserved