Lamellar Hexadecyltrimethylammonium Silicates Derived from Kanemite

Lamellar organoammonium silicates with variable silicon environments have been synthesized by the reaction of a layered polysilicate kanemite with aqueous solutions of hexadecyltrimethylammonium (C 16 TMA) chloride. While the structure of kanemite is composed of only Q 3 silicate species ((SiO) 3 Si O), SiO 4 units with both Q 3 and Q 4 ((SiO) 4 Si ) environments were present in the silicate frameworks of the lamellar C 16 TMA silicates. The Q 4 species mainly formed by intralayer condensation of the Q 3 species in the individual silicate sheets in kanemite rather than by interlayer condensation between the adjacent sheets. The intralayer condensation can be suppressed by lowering the reaction temperature and/or shortening the reaction time, which results in the relative retention of the silicate framework of kanemite in the lamellar C 16 TMA silicates.