壳聚糖/N-乙烯基吡咯烷酮接枝共聚物的制备及其性能

以壳聚糖（CS）和N-乙烯基吡咯烷酮（NVP）为原料，本文采用过氧化氢和抗坏血酸共引发剂引发，制备壳聚糖/N-乙烯基吡咯烷酮的接枝共聚物（CS-g-NVP），研究了引发剂配比、反应温度和反应时间等因素对接枝共聚反应的影响。通过红外光谱、核磁共振和热重分析等对产物进行表征，并考察其吸湿性和亲水性能。结果表明，接枝共聚反应的最佳条件为：引发剂抗坏血酸/过氧化氢的摩尔比为1∶1、反应温度60℃、反应时间12h。接枝共聚产物的吸湿性优于壳聚糖，在饱和氯化钙和饱和硫酸铵环境下产物的吸湿率分别为3.68%和23.1%，高于原料壳聚糖的0.41%和9.77%，产物具有良好的亲水性和水溶性，能溶解于酸性和碱性水溶液中。

Preparation and properties of chitosan/N-vinyl pyrrolidone copolymer

Graft copolymer (CS-g-NVP) was prepared by grafting copolymerization of chitosan (CS) with N-vinyl pyrrolidone (NVP) using hydrogen peroxide/ascorbic acid (H₂O₂/ASA) oxidation-reduction system as initiator. The effects of initiator ratio, reaction time, reaction temperature on the grafting copolymerization process were investigated, respectively. The structure of the graft copolymer was characterized by FTIR, ¹H NMR, TG, and its hygroscopicity and hydrophilicity were explored. The results showed that the optimal reaction conditions of the graft copolymerization were the molar ratio of H₂O₂ to ASA of 1∶1, reaction temperature at 60℃ and reaction time for 12h. The moisture absorption performance of the product was better than that of chitosan. The moisture absorption rates of the products in the saturated calcium chloride and ammonium sulfate solutions were 3.68% and 23.1%, respectively and those of chitosan were 3.68% and 23.1%, suggesting an improved hygroscopicity of the product. The product has good hydrophilicity and water solubility, and can be dissolved in both acidic and alkaline aqueous solutions.