壳聚糖/β-甘油磷酸钠混合比对溶液-凝胶转变性能的影响

Effect of chitosan-sodiumβ-glycerophosphate mixing ratio on the sol-gel transition properties

将质量分数为2%壳聚糖溶液(以浓度为0.1 mol/L的稀盐酸为溶剂)与质量分数为24%的β-甘油磷酸钠(β-GP)水溶液按不同体积比混合后配成壳聚糖/β-GP溶液,再制成壳聚糖/β-GP膜。通过动态流变实验测定壳聚糖/β-GP溶液的储能模量与损耗模量,用SEM、XRD表征壳聚糖/β-GP膜的结构。结果发现,4℃时,壳聚糖/β-GP溶液保持稳定的溶液状态;25℃下壳聚糖/β-GP溶液能保持溶液状态700 s,体积比为6∶4的壳聚糖/β-GP溶液(CP64)开始形成弱凝胶;温度>30℃后,壳聚糖/β-GP溶液迅速发生溶液-凝胶的转变,β-GP溶液加入量的增加不仅能提高溶液-凝胶转变速率,还能使壳聚糖膜的结构更疏松。壳聚糖溶液/β-GP溶液体积比变化能影响溶液-凝胶转变过程,调控壳聚糖/β-GP膜的结构。

Chitosan/sodiumβ-glycerophosphate(β-GP)solution was prepared by addingβ-GP aqueous solution(mass fraction 24%)slowly in chitosan solution(mass fraction 2%with 0.1 mol/L hydrochloric acid solution as solvent)with different volume ratio,and then chitosan/β-GP film was fabricated from the solution obtained above.The storage modulus and loss modulus of chitosan/β-GP solution was analyzed by dynamic geology,and the structure of chitosan/β-GP film was characterized by SEM and XRD.The results showed that the chitosan/β-GP solution was stable at 4℃,while could maintain the stable solution state for700 s at 25℃.The solution with volume ratio of chitosan solution to β-GP solution at 6∶4 formed weak gel(CP64)at 25℃.When the temperature was above 30℃,sol-gel transition occurred quickly.With the amount of β-GP solution added increased,the solution-gel transformation rate was improved and the structure of chitosan film became looser.Therefore,the volume ratio of chitosan/β-GP solution could affect the solution-gel transition process and regulate the structure of chitosan/β-GP membrane.