【摘要】 利用L-亮氨酸和三聚光气反应制备了N-羧基-L-亮氨酸-环内酸酐（NCA）。以聚乙二醇单甲醚（MPEG）为原料,制备了端氨基聚乙二醇单甲醚（MPEG-NH₂）,并以此作为大分子引发剂,在溶液中引发NCA开环聚合,合成了不同组成和分子量的新型两亲性聚L-亮氨酸-聚乙二醇单甲醚两嵌段共聚物（PLM）。利用IR、¹H NMR、DSC、GPC等方法对共聚物结构进行了表征。结果表明,MPEG-NH₂引发NCA开环聚合得到的是嵌段共聚物,通过¹H NMR谱计算得到了共聚物PLM-1、PLM-2和PLM-3中PL链段的摩尔分数分别为7.9％、14.6％和29.8％,共聚物数均分子量（M_n）分别为6 100、7 190和10 420。吸水实验表明,亲水MPEG链段的引入改善了PL的亲水性能,吸水率由7％（PL）提高到24％（PLM-1）。更多还原

【Abstract】 A series of amphiphilic diblock copolymers poly （L-leucine acid ）-b-poly （ethylene glycol） monomethyl ether of lifterent molecular weights were synthesized by the ring-opening polymerization of L-leucine N-carboxy anhydride （NCA） onto amine-terminated poly（ethylene glycol） monomethyl ether （MPEG-NH₂ ） as a macroinitiator. Their structures and properties were characterized by IR, ¹H NMR, DSC, GPC and wateruptake measurements. The results showed that the copolymer samples from the ring opening polymerization of NCA had the expected block structures. The block contents and number-average molecular weights of the copolymers, calculated based on the data of ¹H NMR spectra, could be adjusted by changing the feeding ratio of NCA to the macroinitiator. Owing to incorporation of the hydrophilic MPEG block, the hydrophilicity of these diblock copolymers was much improved than that of the homopolymer poly（L-leucine）.更多还原