论文部分内容阅读
通过固定H_2O2用量为壳聚糖(CS)摩尔单元量的2倍,60℃下氧化降解制备了分子量小于15000的低分子量CS。在低分子量范围内,根据Mark-Houwink方程测定了降解后CS的黏均分子量,并研究了通过控制降解反应时间来调控CS的分子量,结果表明降解反应3h后,CS的黏均分子量变化不大,可降低至5000;在0.5~2.0h之间,CS的黏均分子量与反应时间有着较好的线性关系,线性拟合方程为y=4422.8x+15854,R2=0.9973。该线性方程的建立为低分子量范围内CS分子量的调控制备提供了理论指导。
The low molecular weight CS with molecular weight less than 15000 was prepared by fixing the amount of H 2 O 2 to 2 times the molar amount of chitosan (CS) and oxidative degradation at 60 ℃. In the low molecular weight range, the viscosity-average molecular weight of CS after degradation was determined by Mark-Houwink equation and the molecular weight of CS was controlled by controlling the degradation reaction time. The results showed that the viscosity-average molecular weight of CS did not change much after 3h , Which can be reduced to 5000. Between 0.5 and 2.0h, the viscosity average molecular weight of CS has a good linear relationship with the reaction time. The linear fitting equation is y = 4422.8x + 15854, R2 = 0.9973. The establishment of this linear equation provides a theoretical guide for the preparation and regulation of CS molecular weight in the low molecular weight range.