以辛酸亚锡催化L-丙交酯(L-LA)和ε-已内酯(ε-CL)通过酯交换反应完成本体开环聚合制得可降解的生物医用材料聚(L丙交酯-co-ε-已内酯)(PLLCA),其结构和热性能经1H NMR,高效凝胶色谱和差示扫描量热分析表征.研究了酯交换反应条件对PLLCA力学性能的影响,结果表明,提高聚合温度有利于酯交换反应进行,L-LA和ε-CL的平均嵌段长度减小,PLLCA的玻璃化转变温度(Tg)和拉伸强度也随之减小,断裂伸长率则单调增大;增大ε-CL的投料摩尔分数同样有利于酯交换反应的进行,L-LA的平均嵌段长度随之减小而ε-CL的平均嵌段长度则增大,Tg和拉伸强度均随之减小.%A biodegradable biomedical material, poly( L-lactide-co-ε-caprolactone) (PLLCA) was prepared by transesterification of L-lactide(L-LA) and ff-caprolactone(ε-CL) in bulk open loop u-sing stannous octoate as the catalyst. The structure and thermal properties of PLLCA were characterized by 1 H NMR, gel chromatography and differential scanning calorimetry. Influence of transesterification conditions on mechanical performance of PLLCA were invertigated. The results showed that transesterification was boosted by increase of polymerization temperature and average length of L-LA and ε-CL blocks decreased over the range of 130 ℃ to 150 ℃. Glass transition temperature(Tg) and tensile strength of PLLCA also decreased with increase of the temperature, however, the elongation of PLLCA increased. Increase of ε-CL mole fraction was also beneficial to transesterification, average length of L-LA block decreased over the range of 0. 1 to 0. 9 and average length of ε-CL block increased on the contrary. The Tg and tensile strength of PLLCA also decreased with increase of ε-CL mole fraction.
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