Fabrication of covalently-bonded polystyrene/SiO2 composites by Pickering emulsion polymerization

A novel series of organic-inorganic hybrid materials involving cage-like octa(3-chloroammoniumpropyl)silsesquioxane and Polyvinyl alcohol (OCAPS/PVA) were prepared via solution blending method. The obtained hybrid films were optically transparent and soluble in water. OCAPS/PVA hybrids were characterized by FT-IR, wide-angle X-ray diffraction (WAXD) scanning electronic microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), differential scanning calorimetry (DSC), thermogravimetry analysis (TGA) and tensile test. The results showed that the hydrogen bond interactions were formed between OCAPS and PVA. OCAPS could be dispersed well in PVA matrix till its content was 10 wt%, while the aggregation and crystallization of OCAPS were observed when the content was up to 15 wt%. The glass transition temperature (T (g) ) of OCAPS/PVA was found to increase from 53 A degrees C to 60 A degrees C, and the melting temperature (T (m) ) decreased from 180 A degrees C to 171 A degrees C with increasing OCAPS content from 0 wt% to 15 wt%. The thermal stability of PVA main chain was improved by the addition of OCAPS and the thermal residue ratio also increased. The tensile strength of OCAPS/PVA decreased from 28 MPa to 19 MPa, while the elongation at break of hybrid films increased from 121% to 175%.