ケイ酸塩のケイ酸重合形態(第2報)SiO₂-Al₂O₃系ゲル中の重合ケイ酸の形態分布について

抄録

The polymeric forms of silicic acid in various aluminosilicate gels was investigated by the trimethylsilylation method. Aluminum silicate consists mainly of insoluble polysilicic acids. It also contains some anions, such as SiO₄^4-, oligosilicic acids, and soluble polysilicic acids. On the other hand the aluminosilicate contains mainly anions, such as SiO₄^4-, Si₂O₇^6-, Si₃O₁₀^8-, Si₄O₁₂^8-, and soluble polysilicic acids. It also contains some insoluble polysilicic acids. The molecular distribution of silicic acids in the aluminosilicate was the same as that of the original sodium silicate used in the synthesis. Soluble polysilicic acids were estimated to have a network molecular structure having a molecular formula of Si_2nO_5n+2^{2 (n+2)-}. The average degree of polymerization, 2n, was estimated to be 8.62-15.67.