摘要
将醛基化改性的聚乳酸接枝到壳聚糖,并通过元素分析、红外光谱(IR)、核磁共振(1H-NMR)、X射线衍射(XRD)和热重分析(TG)分别对接枝产物的接枝率、结构和结晶性能进行表征。IR和1H-NMR结果表明聚乳酸成功接枝到壳聚糖主链,不同投料比和接枝率的关系与元素分析一致;PLLA-CHO/CS-NH2最佳摩尔比为1∶2.5,此时的接枝率为52.22%;XRD和TG结果表明接枝产物的结晶度和热分解温度降低,说明壳聚糖的高结晶性得到改善,其应用范围扩大。
A series of chitosan-g-poly(L-lactide)(CS-g-PLLA)copolymers with different grafting percentage were synthesized via modified PLLA.The grafting percentage of the copolymers was analyzed by elementar analyzer,and structure of copolymers was characterized by infrared spectrum(IR) and 1H nuclear magnetic resonance spectrum(1H-NMR).The non-isothermal crystallization and crystallinity behaviors were studied by X-ray diffraction(XRD).The highest grafting percentage of 52.22% was obtained at the molar feed ratio of 1∶2.5(PLLA-CHO∶CS).The results of XRD and thermogravimetry analysis(TG) show that the graft copolymers exhibit low crystallinity and thermal degradation temperature due to the introduction of PLLA.The graft copolymers improve the high crystallinity of chitosan,and expand the application of both chitosan and PLLA.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2009年第12期1-4,共4页
Polymer Materials Science & Engineering
关键词
聚乳酸
壳聚糖
接枝共聚
polylactide
chitosan
graft copolymerization