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Updated: Jan 22, 2026
A Freeze-Thawing Method to Prepare Chitosan-Polyvinyl alcohol Hydrogels Without Crosslinking Agents and Diflunisal Release Studies
Published on: January 14, 2020
Highly water resistant cassava starch/poly(vinyl alcohol) films
Kanda Junlapong1, Phetdaphat Boonsuk1, Chiraphon Chaibundit1
1Department of Materials Science and Technology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, Thailand, 90110.
Abstract:
Biodegradable films were prepared based on cassava starch (CS) and poly(vinyl alcohol) (PVA). To increase its tensile strength and flexibility, CS (20-60 wt%) was blended with PVA at various weight ratios (80-40 wt%). Triethylamine (TEA) was added as a homogeneous catalyst to increase intermolecular interaction and induce miscibility between CS and PVA. The crystallinity and hydrophobicity of blend films containing 20 wt% CS were promoted by the elimination of residual acetate groups in PVA. The number of hydrogen bonds in these blend films increased, which led to stronger interaction and more compact molecular packing between CS and PVA chains. The poor water resistance that limits the shelf-life and applications of CS blends was improved. The addition of TEA to blend films containing 20 wt% CS increased water resistance by 80% and tensile strength by as much as 440%. The development of greater structural integrity yielded ecologically sustainable, low-cost, biodegradable films with excellent physical and mechanical properties.
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