Preparation of poly(vinyl alcohol)/silica nanocomposties by sol-gel method.

The poly(vinyl alcohol)/silica nano-composities hybrid membranes were prepared by co-hydrolysis and co-condensation of ?-glycidyloxypropyl trimethoxysilane (GPTMS) and tetraethoxysilane (TEOS) in poly(vinyl alcohol)(PVA) aqueous solution. The mechanical properties of hybrid membranes was studied, the result indicated that the well dispersion of nanoparticles was beneficial to the enhancement of the mechanical properties, and GPTMS could increase the miscibility of the polymer and SiO₂. The membranes were characterized by scanning eletron microscopy (SEM) equipped with energy dispersive X-ray spectrometry (EDS), ²⁹Si CP/MAS solid-state nuclear magnatic resonance (NMR). The EDS of poly(vinyl alcohol)/silica nano-composities showed that Si element had been grafted onto the chain of PVA. The ²⁹Si CP/MAS solid-state NMR spectra, ¹³C CP/MAS Solid-state NMR spectrum and EDS confirmed that silica had been introduced into the chain of PVA. Latex particle size and morphology was observed by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The TEM and DLS indicated that silica nanoparticles well and regularly dispersed in PVA solution and the average diameter of silica nanoparticles dispersed in PVA solution was about 58 nm. [ABSTRACT FROM AUTHOR]