PVA is a semicrystalline polymer synthesized from the
hydrolysis of polyvinyl acetate. Due to its good solubility,
biocompatibility, and biodegrablility, PVA has been used in
many industrial applications including food, textiles, and
pharmaceutics.18 In addition, polymeric networks among PVA
polymer chains can be formed by chemical reactions or
hydrogen bonding on the pendent OH groups of the repeating
unit in PVA which resulted in cross-linked effects.