Poly(3 trimethoxysilylpropyl methacrylate co dibutyltin maleate)/silica (P(MSMA-co-DBTM)/SiO2)hybrid material has been successfully prepared from the free radical polymerization of MSMA and DBTM monomers in the presence of tetraethoxysilane (TEOS) by in situ sol gel process. The results from scanning electron microscopy (SEM) revealed that the phase separation was located in the nanometer scale. The covalent bond between the organic and inorganic phases was introduced by the co condensation of silanol groups of TEOS and MSMA

which was resulted from the hydrolysis of ethoxysilyl groups or methoxysilyl groups.The hybrid material exhibits optical transparency almost as good as silica gel.The thermalgravimetric analysis(TGA) showed that the two weight loss steps existed.The presence of teh first steps was due to the further condensation of residual silanol groups on the inorganic network during the increase of temperature.