Investigation of Swelling Characteristics of Poly(vinyl alcohol) Hydrogel in different swelling media

摘要

Poly(vinyl alcohol) (PVA) hydrogel was prepared from aqueous solution of the polymer by freezing and thawing method. The effects of PVA concentration and freezing and thawing cycle times on the swelling properties of the PVA hydrogel in distilled water and physiological saline have been investigated. It was shown that the equilibrium swelling ratio of PVA hydrogel in aqueous and physiological saline swelling media decreased with the increase of PVA hydrogel concentration and the freezing and thawing cycle times. After dried by alcohol, the swelling degree of PVA hydrogel in distilled water is larger than that in physiological saline. Based on the analysis of the swelling kinetic equation, the results showed that the swelling behavior of PVA hydrogel in distilled water and physiological saline obeys Fickian diffusion law. The swelling mechanism of PVA hydrogel in distilled water and physiological saline is dominated by diffusion control process.