分离纯化方法对羟丙基壳聚糖结构及取代度测定的影响

张永勤，  张坤

 （青岛科技大学 化工学院， 山东 青岛 266042）

摘要： 提出以醇洗酮沉脱碱法纯化羟丙基壳聚糖（HPCS），并用FTIR、1H NMR谱图和元素分析法的数据与常用的酸中和法相比较。结果表明:该法简便、高效，明显优于酸中和法。由于酸中和法的中和终点较难把握，所得HPCS中极易含有极微量的残留酸而生成—NH+3，从而造成HPCS吸水性的大幅度提高。该结构变化可明显体现在FTIR谱图中，而对1H NMR谱图和元素分析结果无影响，仍可用后两种方法测定其取代度。

关键词： 羟丙基壳聚糖； 分离纯化； 取代度； 中和

 中图分类号： O 636.1          文献标志码：   A

Effect of  Purification Processes on  Structure and DS Assay of Hydroxypropyl Chitosan

  ZHANG Yongqin,  ZHANG Kun

（College of Chemical Engineering,Qingdao University of Science and Technology,Qingdao 266042,China）

Abstract: A dealkalizing method using ethanol washing and acetone precipitation was proposed for the purification of hydroxypropyl chitosan, as comparison with acid neutralizing, using the spetra of FTIR and 1H NMR, and the data of elemental analysis. The results show that this method was more convenient and effective than the acid neutralizing method in which neutralizing end point could hardly be handled, because excess trace amount of H+ could be integrated to —NH2 to produce —NH+3 and greatly increased the hygroscopicity of HPCS. This change was displayed in FTIR spectra significantly. But could not be detected in 1H NMR spectra and elemental analysis, and hence the latter two methods were still accurate for substitution degree of HPCS.

Key words: hydroxypropyl chitosan； purification； degree of substitution； neutralization

 收稿日期： 20140518

作者简介： 张永勤（1965—），女，教授.

文章编号：16726987（2015）03025104； DOI： 10.16351/j.16726987.2015.03.003