SOL-GEL SYNTHESIS OF PHOSPHATE CERAMIC COMPOSITES II

Phosphate ceramics were synthesized using sol-gel technique of direct reaction of P2O5 With tetraethoxy silane (TEOS) or titanium tetraethox ide (Ti(OEt)(4)). The reaction mechanism of P2O5 and TEOS was deduced using liquid and solid-state NMR. Hexacoordinated silicon in phosphosi licate gels was observed. A specially structured titanium phosphate-la yered Ti(HPO4)(2).2H(2)O was synthesized for the first time through th e sol-gel method. The gelation process and phase transformations were investigated.