壳聚糖与丙交酯接枝共聚物的制备与表征

Preparation and Characterization of Chitosan and Lactide Grafted Polymerization Materials

壳聚糖与聚乳酸是具有良好生物相容性的高分子材料,目前被广泛用于生物医学材料,特别是作为组织工程支架。本文以壳聚糖为原料,经过改性制备6-O-三苯甲基-2-邻苯二甲酰基-壳聚糖,作为大分子引发剂,以辛酸亚锡催化D,L-丙交酯接枝聚合,制备共聚物大分子。采用傅立叶变换红外光谱、核磁共振氢谱、碳谱对其结构进行表征,证实了共聚物的生成。热分析测试表明,共聚物具有不同于聚乳酸的热特性,熔点152.8℃。接触角测试表明共聚物具有较好的亲水性。凝胶色谱测定不同反应物配比对共聚物分子量的影响。壳聚糖与丙交酯的接枝共聚物具有较聚乳酸及壳聚糖更为优良的性能,可作为组织工程支架材料。

Chitosan and polylactide are good biocompatible polymers, and are used to apply as biomedical materials, especially as the tissue engineering scaffolds for live cells culture. In this paper, chitosan was firstly modified to form 6-O- triphenylmethyl-2-phthalimido-chitosan as a macroinitiator, and stannous octoate as catalyst, the polylactide-grafted chitosan copolymers were prepared successfully when reacted with D,L lactide. The product molecular structures were proved by FT- IR, ^1H NMR and ^13C NMR. Thermal analysis results show that the copolymers had different TG and DSC curves from PLA and chitosan respectively. The melting point of copolymer stands at 152.8℃. The contact angle measurements demonstrated that the copolymers were more hydrophilic than PLA and its hydrophilicity could be adjusted by the modification degree of chitosan moisty. The GPC determination was used to illuminate the molecular weight distribution of copolymers. Therefore, the grafted polymerization could ameliorate the biocompatibility and improve the mechanical properties than chitosan and PLA, and make the copolymers a new tissue engineering scaffold.