PEG-PDMAEMA-PBMA三嵌段聚合物的合成及其自组装行为

Synthesis of PEG-PDMAEMA-PBMA Triblock Copolymer and Its Self-Assembly

采用连续原子转移自由基聚合途径制备了两亲性三嵌段聚合物聚乙二醇-聚甲基丙烯酸N,N-二甲氨基乙酯-聚甲基丙烯酸正丁酯(PEG-PDMAEMA-PBMA),利用核磁共振氢谱(1 H NMR)和凝胶渗透色谱(GPC)对聚合物结构及分子量进行了表征.动态光散射(DLS)和透射电镜(TEM)结果证实该聚合物的自组装行为具有pH敏感性.通过改变水溶液的pH值可以精确地调控聚合物的自组装行为,从而获得胶束、纳米球、大囊泡和小囊泡等多种自组装结构.这些自组装结构的形成与PDMAEMA链段的质子化程度和聚合物的亲疏水平衡有关.

An amphiphilic triblock copolymer poly（ethylene glycol）-b-poly（2-（dimethylamino） ethylmethacrylate）-b-poly（n-butyl methacrylate）（PEG-PDMAEMA-PBMA） was synthesized by consecutive atom transfer radical polymerization and characterized by 1H NMR and GPC（gel permeation chromatography） techniques.Depending on the environmental pH values,the polymer could self-assemble into micelles,nanospheres,large vecisles and small vesicles.The pH-sensitive self-assembly may be associated with the deprotonated-protonation transition of poly（2-（dimethylamino） ethylmethacrylate） block and the variation of copolymer＇s hydrophilic-hydrophobic balance.