Investigating effect of synthesis conditions on the formation of PVA hydrogel
Abstract
In this study, the poly(vinyl alcohol) (PVA) hydrogel material was prepared via the cyclic freezing-thawing process. Yet the low hydrolysis of commercial PVA made it difficult to form the gel through the cyclic freezing-thawing approach. To increase the hydrolysis degree of PVA, the PVA solution was hydrolyzed in the presence of NaOH. Factors including temperature, time, PVA concentration and the neutralizing acid type were investigated to observe their influence on the hydrolysis degree, the size and distribution of spongy pores. As a result, the PVA hydrogel material with its spongy pore size uniformly distributed from 4 to 20 µm was formed under the hydrolysis condition of 60 oC, six-hour time, and PVA concentration of 6 wt.%. The PVA hydrogel material obtained in this study is therefore suitable for making a biocarrier used in wastewater treatment systems.
Moraref