Alkoxysilyl derivatives of polyhedral oligosilsesquioxanes containing amino and hydroxyl groups and sol-gel hybrid materials on their basis

Abstract

A mixture of polyhedral oligosilsesquioxanes of the empirical formula ((HOCH 2 CH(OH)CH 2 ) 2 N(CH 2 ) 3 SiO 1.5 ) n characterized by narrow molecular-mass distributions has been syn- thesized by the hydrolytic condensation of the product resulting from the interaction of glycidol and 3-amino- propyltriethoxysilane. The said oligosilsesquioxanes have been involved in reaction with 3-isocyanatopropyl- triethoxysilane to give rise to urethane-containing alkoxysilyl derivatives of various degrees of substitution. Organo-inorganic hybrids have been prepared on their basis through the sol-gel method. The structure and properties of the products have been studied by matrix laser desorption/ionization mass spectrometry, GPC, X-ray diffraction, DSC, and thermogravimetry. It has been demonstrated that the properties of the polymer materials thus prepared may be controlled by variation of the ratio of hydroxyl and alkoxysilyl groups in oligosilsesquioxane derivatives and by incorporation of low-molecular-mass sol-gel precursors.