In the present work, the polymer matrix is comprised of Polyvinyl alcohol and natural polymer starch with the addition of an absorbent clay bentonite. These were effectively blended followed by reinforcement in the form of gold, silver, and zinc oxide nanoparticles. Films were prepared and the dispersion of the nanoparticles was studied by scanning electron microscopy and ultraviolet spectroscopy. The mechanical properties and thermal stability of such nanocomposites as compared to the polymeric blend was studied and an enhancement in properties was observed. Furthermore the use of PVA, bentonite and these nanoparticles in facial masks led to the investigation of cosmetic applications of the polymer nanocomposites thus prepared. This composition was found to be stable in face masks for a period of 12 weeks and reported no irritation when applied to the skin.

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Polysilsesquioxanes (PS) powder was synthesized from methyltrimethoxysilane and vinyltrimethoxysilane by hydrolytic condensation method in aqueous phase. The prepared PS powder was characterized using Fourier transform infrared spectroscopy, particle size, and polydispersity of the powders was determined using dynamic light scattering technique. Polydimethylsiloxane (PDMS) nanocomposites and the sealant were synthesized using different weight percentage (1-4 wt %) of PS powder and hydrophobic fumed silica. Tensile strength and thermal stability of the nanocomposites showed perceptible enhancement on increasing the filler ratio when compared to pristine PDMS composites. The surface morphology and the extent of filler dispersion were visualized from the scanning electron microscopy images. Dielectric strength of the composites also showed significant improvement on increasing the filler loading. Poly(methyl/vinyl)silsesquioxane (PMVS) (4 wt %) reinforced composites showed a considerable enrichment in properties when compared to other formulations. Adhesive strength of silicone sealant on both the alumina and mild steel substrate was studied by conducting lap shear test. PMVS-loaded nanocomposites exhibited more adhesive strength on both the substrates and hence it can be used as a sealant in electronic assemblies.

Hydrosilylation method for preparing optically transparent polysilsesquioxane nanosphere reinforced PDMS nanocomposite adhesive with enhanced mechanical, thermal and adhesion properties.

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