Preparation and Characterization of Physically Crosslinked Poly(vinyl alcohol)/ Carboxymethyl Cellulose Hydrogels

摘要

Poly(vinyl alcohol) (PVA) is a semicrystalline synthetic polymer, which can be crosslinked by many different methods to prepare PVA hydrogels, especially, physical crosslinked PVA hydrogels prepared by cyclic freezing/thawing method have shown incredible potential applications in medicine and pharmacy. And compared with chemical crosslinked methods, such as crosslinked by glutaraldehyde and formaldehyde, the physically crosslinked method not only avoid the toxicity of some crosslinkage agents, but also reserve all drug original properties when they used as drug carriers. Carboxymethyl cellulose (CMC) is an important derivative of cellulose, which has shown a large variety of interesting properties for pharmaceutical, food and textile industry applications. Because PVA has no pH-sensitive groups, then the introduction of carboxymethyl cellulose into PVA hydrogels could provide carboxyl groups and make the hydrogels have pH- sensitive properties. So the purpose of the present study was to prepare PVA/CMC composite hydrogels by cyclic freezing/thawing method, then the structure, morphology and thermal properties were characterized by infrared spectra (IR), scanning electron microscope (SEM) and differential scanning calorimetry (DSC). The swelling behavior of the hydrogels in the simulated gastric (pH 1.0) and intestinal (pH 7.4) media was also investigated.