Hybrid materials obtained in microemulsion from methyl methacrylate, methacryloxypropyltrimethoxysilane, tetraethoxysilane

Ternary diagrams for the methyl methacrylate (MMA) (methanol (MeOH)/water a nd tetraethoxysilane (TEOS)/MeOH/water systems were studied. The compositio n domains, where microemulsions form owing to the nanostructures developed by the MeOH-water system, were determined. Refractometric and conductometri c studies showed that water-in-oil (w/o), bicontinuous or oil-in-water)(o/w ) microemulsions may form. Hybrid materials were obtained by the sol-gel re action of TEOS combined with the free-radical copolymerization of MMA and m ethacryloxypropyltrimethoxysilane (MPS). MPS was added in order to avoid ph ase separation. The change of the glass transition temperature and of the t hermal stability of the organic network in the presence of the inorganic on e, and the similar forming mechanisms and rates proved the formation of sim ultaneous interpenetrating polymerinorganic networks. (C) 1999 Elsevier Sci ence Ltd. All rights reserved.