戊二醛对壳聚糖交联聚乙烯吡咯烷酮水凝胶结构和性能的影响

目的]把聚乙烯吡咯烷酮与壳聚糖的大分子链进行交联,破坏壳聚糖大分子链的规整结构,增强壳聚糖的亲水性,改善对脂肪的吸附能力。方法]以戊二醛为交联剂,通过壳聚糖大分子链的羟基和氨基,在壳聚糖大分子链之间形成化学交联点,同时网络聚乙烯吡咯烷酮,形成半互穿网络结构,合成聚乙烯吡咯烷酮(PVP)/壳聚糖(CS)交联水凝胶。最后,考察交联剂的用量对凝胶溶胀度和脂肪吸附能力的影响。结果]红外光谱分析证明发生了交联反应,形成半互穿网络结构。SEM照片观察到PVP/CS交联凝胶表面呈微相分离。性能的测定结果表明,该凝胶在水中有很好的溶胀性,当交联剂的用量为2.5 ml时,凝胶的溶胀度最大。结论]壳聚糖交联聚维酮凝胶对脂肪的吸附能力比起单纯的壳聚糖有很大的提高。

Influence of Glutaraldehyde on Structure and Properties of Chitosan and Polyvinylpyrrolidone Cross-linked Hydrogel

Objective]The research aimed to destroy tacticity of chitosan macromolecular chain,enhance the chitosan hydrophilicity and improve the adsorption ability of fat by crosslinking chitosan macromolecular chain with polyvinylpyrrolidone.Method]A type chitosan and polyvinylpyrrolidone cross-linked hydrogel was prepared by chemical modification method through hydroxy and amino groups on chitosan macromolecular chain with glutaraldehyde as cross-linking reagent,which forms an semi-interpenetrating polymer network.PVP/CS hydrogel was characterized by the infrared spectra to make clear crosslinking reaction to form semi-interpenetrating network structure.The influence of cross-linking reagent weight on swelling properties and fat-binding capacity（FBC） of the hydrogels was studied.Result]Microzone of CS and PVP were observed over the surface of hydrogel from SEM micrographs.SEM test indicated that the hydrogel surface of cross-linked chitosan with polyvinylpyrrolidone had micro-phase separation structure which would effect its swelling properties and fat-binding capacity（FBC）.Performance measurement test showed that the swelling degree of the hydrogels reached to the maximum when the amount of glutaraldehyde was 2.5 ml.Conclusion]FBC of the hydrogels had been greatly improved than that of chitosan.