Structure of hybrids based on TEOS-cyclic forms of siloxane system

Hybrid glasses based on tetraethoxysilane (TEOS) modified by addition of selected cyclosiloxanes have been prepared by sol-gel method. Octamethylcyclotetrasiloxane (N) and 2,4,6,8-tetramethyl-2,4,6,8-tetravinylsiloxane (VMC) have been chosen as an organic modifier of the silica matrix. Molar ratio of TEOS to cyclosiloxane varied from 1 0 to 1 0 5. Structure of prepared hybrids has been studied by infrared spectroscopy (FTIR), photoelectron spectroscopy (XPS) and nuclear magnetic resonance spectroscopy (NMR). Optical properties of bulk glasses in the visible range have also been reported. (C) 2009 Elsevier B.V. All rights reserved