Catalytic Effect of Chemically Modified Metal Alkoxides on Hydrolysis and Condensation Reactions of Methyl- and Phenyl-Ethoxysilanes

Shingo KATAYAMA, Ikuko YOSHINAGA, Yuji KUBO, Noriko YAMADA
2003 Journal of the Ceramic Society of Japan  
The catalytic eect of chemically modied metal alkoxides on the hydrolysis and condensation reactions of methylethoxysilanes and phenylethoxysilanes was investigated by 29 Si nuclear magnetic resonance spec troscopy and gel permeation chromatography. Metal alkoxides such as Al(OsecC 4 H 9 ) 3 , Ti(OisoC 3 H 7 ) 4 and Nb(OC 2 H 5 ) 5 modied with ethyl acetoacetate accelerated not only the condensation reactions but also the hydrolysis reactions of methyl and phenylalkoxysilanes. The catalytic
more » ... . The catalytic eect of these metal alkoxides was found to be dierent between methyl and phenylalkoxysilanes. The catalytic activity increases in the order of NbAlTi alkoxides in the case of methylethoxysilanes, whereas in the case of phenylethoxysilanes it increases in the order of NbTiAl alkoxides. The dierence in catalytic activity was discussed on the basis of the partial charge of M in metal alkoxide, the dierence in electronegativity between M and Si and the dierence between the coordination number and valence of M.
doi:10.2109/jcersj.111.743 fatcat:6unnf5hv2zd4hiauifilxjojeu