Preparation of poly(methyl acrylate-co-itaconic anhydride)/SiO2 hybrid materials via the sol-gel process - The effect of the coupling agent, inorganic content, and nature of the catalyst

Transparent poly(methyl acrylate-co-itaconic anhydride)/SiO2 hybrid materia ls were prepared from methyl acrylate-itaconic anhydride copolymer and tetr aethoxysilane (TEOS:) with the coupling agent (3-aminopropyl)triethoxysilan e (APTES) via a sol-gel process. The covalent bonds between the organic and inorganic phases were introduced by the in situ aminolysis of the itaconic anhydride units with APTES forming a copolymer bearing a triethoxysilyl gr oup. These groups subsequently were hydrolyzed with TEOS and allowed to for m a network. These reactions were monitored by Fourier transform infrared a nalysis. The amount of APTES had a dramatic influence on the gel time and s ol fraction. The effect of APTES, the inorganic content, and the nature of the catalyst on the thermal properties and morphology of the hybrid materia ls were studied by differential scanning calorimetry, thermogravimetric ana lysis, scanning electron microscopy, and atomic force microscopy. (C) 2000 John Wiley & Sons, Inc.