Textural properties of silica-based organic-inorganic polymer hybrid xerogels

Samples of xerogels containing organic polymers were prepared by the sol-gel method via the reac-tion of tetraethoxysilane (TEOS) and organic monomers with an acidic catalyst. These materials were obtained as transparent and homogeneous bulk materials. The samples were characterized by Raman and IR spectroscopies, N2-adsorption (77 K), and atomic force microscopy (AFM). Specific surface areas and porosities of the samples were estimated from nitrogen adsorption-desorption isotherms at 77 K. Textural properties such as specific surface areas (SBET), pore volume (Vp), average pore sizes (Rp), and micropore volume (VDR) were obtained. The complete adsorption-desorption isotherms and pore size distributions were analysed following the Dollimore–Heal method. Atomic force microscopy was used to investigate the morphology and roughness of the samples. Key words: organic–inorganic polymer hybrid materials, sol-gel process, photo-polymerisation, organi-cally modified silicates, porosity, roughnes