Growth of SiOC/SiC nanostructures from cured polysiloxane-silica composite. Issue 3 (15th February 2018) - Indulekha, K.
Abstract: SiOC/SiC nanostructures were produced by the pyrolysis of silica reinforced silicone polymer cured through platinum catalyzed hydrosilylation route. The base polymers used were vinyl terminated poly(dimethyl-co-diphenyl) siloxane (V-PMPS) and trimethylsilyl terminated poly(dimethyl-co-diphenyl-co-methyl hydrogen) siloxane (TMS-PMPHS). While TMS-PMPHS was synthesised from non-halogenated precursors by acid catalyzed ring opening/co-condensation approach, V-PMPS was used as received. The cured polymers were characterised for their spectral and thermal properties. Incorporation of silica filler to V-PDMS resulted in composite with higher onset of decomposition temperature compared to the unfilled counterpart. Pyrolysis of the filled polymer was carried out at different temperatures and the products were analysed by FTIR, Raman spectroscopy, XRD, FESEM and EDAX. It was found that one dimensional ceramic nanostructures are produced from the silica filled composite at lower temperature of 900 °C compared to the unfilled system. The size of the nanostructures increased with increase in the pyrolysis temperature.