微波-H_2O_2联合降解法制备分子量可控的窄分布壳聚糖及其阻垢性能探索

Preparation of Oligochitosan with Narrow Distribution of Molecular Weight by Microwave-H_2O_2Degradation and Therein Antiscaling Activity Exploration

采用微波-H2O2联合降解法,在均相条件下制备窄分布的低分子量壳聚糖,研究了H2O2浓度、辐射阳极电流、辐射时间以及体系温度对壳聚糖降解的影响。结果表明,降解产物的分子量可以通过实验参数的变化进行调控,且重复性较好。通过FT-IR、XRD对低聚壳聚糖进行了结构表征,证明降解前后壳聚糖的基本化学结构没有改变,只是聚合度发生了变化。当H2O2浓度为4%,辐射阳极电流为70 mA,辐射时间为6 min,体系温度控制在70℃时,能够得到分子量6000左右的低聚壳聚糖,此产品具有一定的阻垢性能。

Oligochitosan with narrow distribution of molecular weight was prepared by microwave-H2O2 degradation under homogeneous conditions. The effect of H2O2 concentration, anode radiation current, irradiation time and temperature on the degradation of chitosan were investigated. The results showed that the molecular weight of resulting oligochitosan can be controlled and the repeatability of molecular weight and its distribution was good. Chitosan and oligochitosan were characterized by IR and XRD analysis, and it was found that ouly the degree of polymerization was changed and the basic pyranride monosaccaride unit structure from chitosan was totally unchanged before and after degradation. The oligochi- tosan with a molecular weight of around 6000 can be obtained with a H2O2 concentration of 4%, an anode radiation current of 70 mA at 70℃ within a radiation period of 6rain. The degradating product was soluble and exhibited some scale inhibitory activity.