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-functionalized styrene-ethylene-butylene-styrene block copolymer (SEBS elastomer) with tetrabutyl titanate and tetraethoxysilane. SEBS was modified via nitration and subsequent reduction, giving the product SEBS II bearing amino groups in the hard segments. The trimethoxylsilane functionalization 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 properties. Electron micrographs clearly show that the size of dispersed inorganic phase can be reduced by the use of trimethoxyl silane functionalization. The results of dynamic mechanical analysis are also discussed. (C) 1997 John Wiley & Sons, Inc.Polymer ScienceSCI(E)23ARTICLE5853-8606