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The multi-faceted oligomeric silsesquioxane (Polyhedral oligomeric silsesquioxane POSS, also known as a clathrate sesquioleate siloxane) having a considerable symmetry nanostructures, the inorganic skeleton formed by the short chain of the three - dimensional Si-O-Si ( kernel) and covering it completely organic substituent (housing) . Vertex is an inert organic group or a reactive functional group , substituents may be different based on its vertex substituent can be prepared by a series of POSS / polymer composite. Thermal properties, mechanical properties , such as the POSS groups introduced into the polymer , the polymer can often be significantly improved , so POSS polymer of research in recent years has aroused great interest . The paper introduces the structure , synthesis methods and performance characteristics of the POSS expounded the significance of the organic-inorganic hybrid materials and POSS / polymer composite material synthesis and its development trend . Adopt commercialization POSS ( R 7 the ( Si 8 O 12 < / sub > ) , of C 3 H 5 < isobutyl / sub>, R group is not reactive , functional groups are allyl) by emulsion polymerization, prepared POSS / composite material , polystyrene (PS) , and by FTIR, NMR, a laser particle size analyzer , TEM, DSC and test methods of characterization and properties of composites . The test results show that its particles are monodisperse , morphological rules . POSS / PS composite material we prepared a glass transition temperature of the improved 15 ° C and compared to the PS with the same method , . In addition, under certain conditions, condensation system containing eight -Cl POSS , by atom transfer radical polymerization ( ATRP ) , novel structure POSS / PS composites . And adjusting the reaction time to obtain a composite material of different molecular weights , and the products were characterized by IR, NMR, GPC, DSC and TG techniques and performance testing . The results showed that the product yield , the molecular weight and glass transition temperature increases with the reaction time . Thermal properties of the composite material than the PS prepared under the same conditions have improved significantly.
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