Abstract
Papers related to syntheses of silicate esters, the formation of polysilicate esters and the polycondensation of them are abstracted and some applications of these esters are listed up. The physical and chemical stability of polysilicate ester depends upon the steric effect of alkoxyl group and the derivatives having bulky group show excellent properties such as high hydrolytic and thermal resistance. It is presented that both the hydrolysis and the condensation reaction of silicate ester pass through five co-ordinated in-termediate and the functionality of silicic acid in the condensation reaction is below 3. 5. The formation of polysilicic acid does not occur by the successive condensation mechanism of ortho silicic acid while that is carried out via oligomer of silicic acid, especially cyclic tetramer as a secondary construction unit derived from the monomer. This reaction strongly undergoes the effect of pH. It is found that under the condition of neutral, the stabilization of silicic acid in a solution is increased with the presence of hydrogen bonding agents, methanol and chromic acid while the addition of multivalent cations accelerates gelation.
