Preparation and Properties of Silicon- Containing Polymer Hybrids from 3-Methacryloxypropyltrimethoxysilane

The preparation of organic–inorganic polymer hybrids consisting of carbon–carbon and siloxane chains was investigated by radical polymerization of 3-methacryloxypropyltrimethoxysilane (MAS) followed by acid-catalyzed hydrolytic polycondensation. The condensation of poly(3-methacryloxypropyltrimethoxysilane) (S-PMA) of various molecular weights Mn = 830–12000 prepared by polyaddition provided transparent and flexible free-standing hybrid gel films. The mechanical properties of these films were highly dependent on the carbon–carbon chain length: with an increase in the carbon– carbon chain length, the elasticity of gel films increased, while the tensile strength and Young’s modulus decreased. Hydrolyzability of S-PMA decreased with an increase in the carbon–carbon chain length, resulting in the formation of rubber-like films with flexibility. # 1998 John Wiley & Sons, Ltd.