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Synthesis of poly(vinyl alcohol) / silica gel polymer hybrids by in-situ hydrolysis method

โœ Scribed by Ryo Tamaki; Yoshiki Chujo


Publisher
John Wiley and Sons
Year
1998
Tongue
English
Weight
304 KB
Volume
12
Category
Article
ISSN
0268-2605

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โœฆ Synopsis


Homogeneous poly(vinyl alcohol) (PVA)-silica gel polymer hybrids were prepared by in-situ hydrolysis of poly(vinyl acetate) (PVAc) in a solgel reaction mixture with tetramethoxysilane (TMOS). The degree of hydrolysis was evaluated by FTIR and 13 C CP/MAS NMR; it increased with an increase in the acid catalyst and reached 85% with 1.6 ml of 0.1 M HCl. The homogeneity of the polymer hybrids obtained was maintained when the reaction was performed at 60 ยฐC. However, the polymer hybrid became turbid with an increase of the amount of catalyst present when the reaction was conducted at room temperature. The homogeneity of the polymer hybrids obtained was evaluated by nitrogen sorption porosimetry of a porous silica that was obtained by charring the PVA hybrid. The results confirmed the molecular-level dispersion of the PVA in the hybrid.


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