壳聚糖论文壳聚糖的改性研究.docVIP

壳聚糖论文：壳聚糖的改性研究 【中文摘要】本论文首先利用甲氧基聚乙二醇(mPEG)改善壳聚糖的水溶性。将不同分子量的mPEG的羟基羧化后,与壳聚糖分子链上3位羟基发生酯化反应,制备出梳形可分散于水的甲氧基聚乙二醇接枝壳聚糖(CS-g-mPEG)。采用红外光谱(IR)、核磁共振(1H-NMR)对CS-g-mPEG的结构进行了表征,结果表明这种方法可以成功制备CS-g-mPEG。接枝共聚物水溶性实验表明,CS-g-mPEG接枝共聚物的溶解性得到显著提高。为了改善壳聚糖的脂溶性,本论文在壳聚糖上面引入聚乳酸,壳聚糖上的羟基引发丙交酯开环聚合得到壳聚糖-聚乳酸(CS-g-PLA)接枝共聚物。采用红外光谱(IR)和核磁共振(1H-NMR)表征了接枝共聚物的结构。共聚物的脂溶性实验表明,壳聚糖接枝聚乳酸后可以溶解在部分有机溶剂中。另外,本文还利用胺解技术在聚乳酸膜表面引入自由氨基,再利用戊二醛将氨基转化为自由醛基,然后用壳聚糖涂层的方法,制备了壳聚糖表面改性的聚乳酸膜载体。采用红外光谱(IR)对改性聚乳酸膜的结构进行分析表征。结果表明,壳聚糖可以成功固定在聚乳酸膜表面。壳聚糖接枝聚乳酸膜表面后可以改善聚乳酸的生物相容性。 【英文摘要】Firstly, water solubility of the chitosan was improved by methoxy poly(ethylene glycol)(mPEG) in this paper. mPEG with different molecular weights after carboxylated was occurred esterification reaction to the hydroxyl groups at C-3 on the chitosan backbone, and the comb-shaped methoxy poly(ethylene glycol) grafted chitosan(CS-g-mPEG) which can be dispersed in water was prepared. The structure of CS-g-mPEG was characterized by infrared spectroscopy (IR) and nuclear magnetic resonance(扝-NMR), and the results showed that CS-g-mPEG can be successfully prepared by this method. Water-soluble experiment of the graft copolymer showed that the solubility of the CS-g-mPEG graft copolymer was improved significantly.polylactide(PLA) was introduced to chitosan, and the graft copolymer of chitosan-g-polylactide(CS-g-PLA) was synthesized successfully through ringopening polymerization by the hydroxyl group of the chitosan initiated, in order to improve fat solubility. The structure of this graft copolymer was characterized by IR and 1H-NMR. Fat-soluble experiment of the copolymer showed that chitosan grafted PLA can dissolve in partial organic solvents.In addition, in this paper, the free amino was introducd to the surface of the PLA membrane by using aminolysis technique, and amino group was transformed into adehyde group by using glutaraldehyde, then chitosan-modified PLA membrane was fabricated by chitosan-coating technique. The structure of the modified PLA was char