聚乙烯醇/壳聚糖凝胶的制备及性能研究

Preparation and properties of chitosan-polyvinyl alcohol hydrogels

通过壳聚糖与聚乙烯醇共混,用戊二醛作交联剂制备了聚乙烯醇/壳聚糖凝胶,并考察了不同质量比、交联剂浓度以及温度对凝胶的硬度和溶胀性能的影响。结果表明:随着聚乙烯醇与壳聚糖的质量比、交联剂浓度的增大,凝胶的硬度增大而溶胀性能减小。随着成胶温度的升高,凝胶的硬度和溶胀性能均先增大后减小。在此基础上,通过两种方法将银粒子分散到凝胶中:(1)在成胶过程中加入硝酸银,成胶后用还原剂硼氢化钠还原;(2)制成凝胶以后,将凝胶依次浸泡在硝酸银和硼氢化钠溶液中。通过XRD和SEM表征,说明两种方法均能将银粒子均匀分散在凝胶中,从而表明壳聚糖凝胶可以作为金属纳米粒子的载体,这将在生物医学方面具有良好的应用前景。

Chitosan-polyvinyl alcohol hydrogel was prepared by using glutaral as crosslinker and the effects of the mass ratio of polyvinyl alcohol and chitosan, the concentration of crosslinker, and the temperature on the hardness and swelling ratio of the hydrogels was investigated. The results showed that the hardness of chitosan-polyvinyl alcohol hydro- gel increased and the swelling ratio reduced with increasing the mass ratio of polyvinyl aleoholand-chilosan and the concen- tration of crosslinker. With elevating the reacting temperature, the hargness and swelling property increased firstly, and then decreased. Based on the study on the hardness and swellingproperties of chitosan-polyvinyl alcohol hydrogel, two methods was used to prepare the composite hydrogel filled by Ag nano-particles, namely, AgNO3 was added into the hy- drogel during reacting process, then reduced by NaBH4 and secondly, the freshly swollen hydrogel was orderly socked in AgNO3 and NaBH4 solution to product the Ag nano-particles. The XRD and SEM indiceted that the Ag nano-partiles was successfully dispersed into the hydrogel homogeneously, proving the chitosan can be used as the carrier of Ag nano-parti- cles goodly applying for biology and medical aspest.