作　　者： ; ; ; ; ;

机构地区： 暨南大学生命科学技术学院化学系

出　　处： 《高分子学报》 2005年第3期327-332,共6页

摘　　要： 以聚乙二醇(PEG)和N -苄氧羰基 -L- 天冬氨酸酐为原料,通过溶液缩聚法制备了聚(聚乙二醇 -co -L -天冬氨酸)交替预聚物(PEG- ASP) n;进一步以辛酸亚锡为催化剂、(PEG- ASP) n 为共引发剂引发D ,L- LA和GA开环共聚合成了带有侧氨基功能基团的PLGA (PEG- ASP) n 共聚物.用GPC、FT -IR、1 H -NMR、DSC等研究了共聚物的结构和性能.结果表明,共聚物表现为典型的无定形聚合物;(PEG- ASP) n 的含量对共聚物的性能有显著影响,随(PEG- ASP) n 含量增加,共聚物的亲水性增强,玻璃化转变温度(Tg)下降;以Pd(5wt% ) C为催化剂,采用催化加氢方法可完全脱除共聚物侧氨基上的保护基团;脱除侧氨基上的保护基团后,共聚物的分子量和Tg 值均略有增大,亲水性有所提高. Poly (poly (ethylene glycol) -co-L-aspartic acid) (PEG-ASP), alternating prepolymer was first prepared by the solution polycondensation from N-(benzyloxycarbonyl)-L-aspartic acid anhydride and poly(ethylene glycol). Then, the novel PLGA-( PEG-ASP). copolymers with pendant amine functional groups were synthesized by bulk ring-opening copolymerization of D, L-LA with GA using tin octoate(Sn(Oct)(2)) as a catalyst, and (PEG-ASP)(n) prepolymer as a co-initiator. The structure and properties of the novel copolymers were studied by GPC, Fr-IR,H-1-NMR and DSC, etc. Results showed that the PLGA- (PEG-ASP). copolymers were typical amorphous polymers. The content of ( PEG-ASP), prepolymer had significant influence on the properties of the copolymers. The hydrophilicity of the copolymers was improved and the value of the glass transition temperature(T-g) decreased as the content of the prepolymer increased. The benzyloxycarbonyl (CBz) protecting groups of the copolymer were totally removed by catalytic transfer hydrogenation using palladium over activated carbon (5 wt%) as a catalyst and H-2 as an effective hydrogen donor. The molecular weight,the value of T-g and hydrophilicity of the copolymer were somewhat increased as the CBz protecting groups were removed.

关 键 词： 共聚物 合成与表征 氨基 聚乙二醇 玻璃化转变温度 侧链 天冬氨酸 无定形聚合物 保护基团 溶液缩聚法 结构和性能 辛酸亚锡 共引发剂 功能基团 共聚合成 加氢方法 催化剂 亲水性 预聚物 分子量

领　　域： [理学] [理学] [理学] [理学]