²⁹Si NMRによるエトキシトリメチルシランとアルカリ金属イオンとの反応挙動解析

抄録

The reactions between ethoxytrimethylsilane and alkali ions were investigated by ²⁹Si NMR to evaluate the formation of Si-O-M (M: alkali metal) linkage. The difference in the reactions among alkali species was also discussed. The formation of the linkage was influenced by the pH of reaction mixture. The shift of NMR signal to higher magnetic field, which can be ascribed to linkage processes, was observed in the solution with pH greater than 13.1. The magnitude of the shift arising from the addition of alkali ions increased in the order of Na⁺, K⁺ and Li⁺. In the solution containing alkali ions, the efficient shielding of Si nuclei also increased in this order, which confirmed the strong Si-O-M linkage. However, little difference in the formation rates between Si-O-Na and Si-O-K was observed and the formation processes of Si-O-Li, Si-O-Na and Si-O-K were considered to be identical.