Abstract
The sol-gel reaction of bisphenol-A type polycarbonate (PC) oligomer (PCS) having triethoxysilyl groups at both chain ends and that of PCS with tetraethoxysilane (TEOS) or tetramethoxysilane oligomer provided two types of silica films containing organic-inorganic hybrid materials; the former low silica (PCS-HM) and the latter high silica (HSPC-HM), respectively. The PCS-HM film was superior to the PC film and inferior to the HSPC-HM film in terms of morphological homogeneity, heat resistance, mechanical strength, and surface hardness. The HSPC-HM films had the minimum oxygen permeability at a PCS/TEOS weight ratio of 3/7. On the other hand, Si concentration-gradated hybrid materials obtained by consecutively coating HSPC-HMs having various PCS/TEOS weight ratios had large thermal shock resistance and its silica surface was stable to organic solvents.
