Journal of Applied Polymer Science, Vol.115, No.4, 2212-2220, 2010
Study on Thermal Enhancement Mechanism of POSS-Containing Hybrid Nanocomposites and Relationship Between Thermal Properties and their Molecular Structure
In this study, a series of poly(4-acetoxystyrene) (PAS)-octavinyl polyhedral oligomeric silsesquioxane (POSS) blends and the polystyrene (PS)-octavinyl POSS blends were prepared by the solution-blending method and characterized with Fourier transform infrared (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) techniques. The results show that the glass-transition temperature (T-g) of the PAS-POSS blends increases at a relatively low POSS content and then decreases at a relatively high POSS content. POSS can effectively improve the thermal stability of the PAS-POSS blends at low POSS content, and T-g of PAS-POSS blends decreases with the increase in POSS content at relatively high POSS content. However, the T-g of the PS-POSS blends persistently decreases even at very low POSS content. T-g change mechanism was investigated in detail by XRD, TEM, and FTIR spectra. The influence mechanism of POSS content and dispersion in composites, and parent polymer structure on thermal properties of the blends was investigated in detail. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 115:2212-2220, 2010