New synthetic route to (3-glycidoxypropyl)trimethoxysilane-base hybrid organic-inorganic materials

Hybrid organic-inorganic materials have been obtained by cohydrolysis of(3- glycidoxypropyl)trimethoxysilane (GPTMS) and tetraethyl orthosilicate (TEOS ) in acidic conditions. Boron trifluoride diethyl etherate (BF3OEt2)has bee n used to catalyze the epoxide polymerization. The effect of BF3OEt2 has be en studied by multinuclear magnetic resonance (NMR) in the precursor sol an d by Fourier transform infrared spectroscopy in the final material. The add ition of BF3OEt2 to a prereacted sol of CPTMS and TEOS has allowed the epox ide ring opening at room temperature, without formation of diol units or bo ric acid precipitation in the final material. The prereaction;ion time of G PTMS with TEOS has been found to be an important parameter. The catalytic e ffect of BF3OEt2 with respect to other commonly used catalysts in sol-gel p rocessing of GPTMS-based hybrid organic-inorganic materials, such as zircon ium butoxide and 1-methylimidazole, has been studied.