Preparation and properties of organic–inorganic hybrid materials using titanium phosphonate cluster

Abstract

Organic–inorganic hybrids containing [Ti4(μ3-O)(OiPr)5(μ-OiPr)3(O3PPh)3]·thf as element-blocks were prepared by hybridization with poly(dimethylsiloxane), poly(methylsilsesquioxane), poly(ethoxysilsesquioxane), poly(methyl methacrylate), poly(vinyl alcohol), poly(4-vinylphenol), poly(styrene-co-allyl alcohol) or poly(bisphenol A-co-epichlorohydrin). The concentration of the titanium cluster was increased to 40 wt% to form crack-free films with high transparency. The temperature at which 10 wt% weight loss occurred increased with the concentration of the titanium cluster because an alcohol exchange reaction was expected between the titanium cluster and polymers. The mechanical strengths and strains of poly(dimethylsiloxane) hybrids were very low. The tensile strengths and elongations of poly(methyl methacrylate) hybrids increased with the increase in the titanium cluster concentration. The tensile strengths and elongations of poly(vinyl alcohol) hybrids were highest when the titanium cluster concentration was 10 wt%. Organic–inorganic hybrids containing [Ti4(μ3-O)(OiPr)5(μ-OiPr)3(O3PPh)3]·thf (TiOPPh) as element-blocks were prepared by hybridization with silicone polymers (poly(dimethylsiloxane) (PDMS), poly(methylsilsesquioxane) (PMS) or poly(ethoxysilsesquioxane) (PEOS)), the hydroxyl groups substituted organic polymers (poly(vinyl alcohol) (PVA), poly(4-vinylphenol), poly(styrene-co-allyl alcohol) or poly(bisphenol A-co-epichlorohydrin) (PBE)) or poly(methyl methacrylate) (PMMA). The concentration of TiOPPh was increased to 40 wt% to form free-standing hybrid films with PDMS, PMS, PVA and PBE polymers. The tensile strengths and elongations of PMMA and PVA films were higher improved than only polymers because TiOPPh acted good crosslinkers.