Interlayer Silylation of Layered Octosilicate with Organoalkoxysilanes: Effects of Tetrabutylammonium Fluoride as a Catalyst and the Functional Groups of Silanes

Abstract Interlayer silylation of layered sodium octosilicate (Na‐Oct) with various organoalkoxysilanes was conducted using hexadecyltrimethylammonium ion‐exchanged layered octosilicate (C 16 TMA‐Oct) as an intermediate in the presence or absence of tetrabutylammonium fluoride (TBAF). The degree of silylation was increased by adding TBAF. It is suggested that F − ions perform a nucleophilic attack on the alkoxysilanes, which promotes the silylation reaction. C 16 TMA‐Oct was silylated with octyltriethoxysilane (C 8 TES) or 3‐mercaptopropyltriethoxysilane (MPTES) to compare the reactivity of the two organoalkoxysilanes in the presence or absence of TBAF. A higher degree of silylation of C 16 TMA‐Oct was observed with MPTES, suggesting the higher accessibility of this silylating agent into the interlayer polar region of C 16 TMA‐Oct. Overall TBAF appears as a relevant catalyst for the covalent interlayer surface modification of layered silicates with organic functional groups.