Porous Tubular PVA Hydrogels: Preparation and Assessment

Abstract

Hydrogels have been used in related biomedical fields, and their pore size and structure are an important investigation emphasis in relative studies. Hydrogels with different pore sizes have different applications. This study aims to examine the pore size and porosity of the polyvinyl alcohol (PVA) tubular hydrogels. Sodium chloride (NaCl) with different concentrations serves as the porogen while polyvinylpyrrolidone (PVP) serves as the surfactant. PVA is made into tubular hydrogels via a freeze-thaw method and the cross-linking with glutaraldehyde. The hydrogels are then processed with an ultrasonic vibration in order to remove the residual solvents and the porogens, in order to obtain tubular PVA hydrogels with an interconnected porous structure. The test results indicate that the porosity and pore size of the PVA hydrogels significantly increase as a result of the uses of a porogen. Excessive NaCl as a porogen damages the porous structure of hydrogels, which in turn decreases the porosity and pore size of the hydrogels.