NEW HYBRID MATERIALS INCORPORATING TETRABUTYL TITANATE AND TETRAETHOXYSILANE WITH FUNCTIONAL SEBS ELASTOMER VIA THE SOL-GEL PROCESS - SYNTHESIS AND CHARACTERIZATION

New flexible hybrid materials were prepared by incorporating amino-fun ctionalized styrene-ethylene-butylene-styrene block copolymer (SEBS el astomer) with tetrabutyl titanate and tetraethoxysilane. SEBS was modi fied via nitration and subsequent reduction, giving the product SEBS I I bearing amino groups in the hard segments. The trimethoxylsilane fun ctionalization was then achieved by the addition of coupling agent, 3- glycidyloxypropyl trimethoxysilane (GOTMS) in the sol-gel processing. The hydrolytic condensation of these trimethoxylsilane groups on SEBS II with metal alkoxide led to the formation of covalent bonds between the organic polymer chains and the inorganic networks produced in situ to prevent macrophase separation, resulting in better optical propert ies. Electron micrographs clearly show that the size of dispersed inor ganic phase can be reduced by the use of trimethoxyl silane functional ization. The results of dynamic mechanical analysis are also discussed . (C) 1997 John Wiley & Sons, Inc.