A Novel Method for Preparing Poly(vinyl alcohol) Hydrogels: Preparation, Characterization, and Application

This work provides a new method to prepare poly(vinyl alcohol) (PVA) hydrogel. Compared with the traditional repeated freeze–thaw method, the physical cross-linking method was adopted to prepare a high-strength hydrogel in one step. The morphology, melting, and crystallization behavior and mechanical properties of the hydrogel were investigated. The hydrogel has a high water content and reswelling rate, as well as a high melting temperature and mechanical strength. It also has a stable cross-linked structure in the temperature range of 25–65 °C. The hydrogel fracture surface shows ductile and brittle fracture morphology. The protrusions in the hydrogel three-dimensional topography are more numerous and homogeneous when the solvent preparation ratio is 4–6. On the basis of the good plasticity of the hydrogels, tubular hydrogels with inner diameters of 1–6 mm are also prepared to widen their applications.