Preparation of Silica-Pillared Fluorohectorite by Cointercalation of Polysiloxane and Polyvinyl Alcohol

Abstract

Silica-pillared clays with mesopores were prepared from fluorohectorite, aminopropyltriethoxysilane (APS) and tetraethoxysilane (TEOS) affected using polyvinyl alcohol (PVA). The presence of PVA was important in this synthesis and was effective on the porosity of the obtained silica-pillared clays. Based on the X-ray diffraction measurements, the basal spacings of the silica-pillared clays increased from 1.7 to 5.6 nm with an increase in the PVA concentration. As with the basal spacings, the peaks of the pore size distribution and the average pore diameter shifted up to approximately 3 nm. The pore volumes corresponded to the basal spacings expanded by cointercalation of PVA and polysiloxane. The pore properties and structures of the pillared clays were investigated and the results indicated the relation between the layer structure and pore structure.