以二硫键连接的两嵌段共聚物的制备新方法  

Novel Method of Preparation of Diblock Copolymers with Disulfide Bonds at Junction Points

作　　者：张丽鑫[1] 王金涛[2] 杨永芳[1] 赵汉英[2] 

机构地区：[1]河北工业大学化工学院高分子科学与工程系,天津300130 [2]南开大学化学学院,天津300071

出　　处：《高等学校化学学报》2016年第1期161-166,共6页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:51473079)资助~~

摘　　要：报道了一种制备二硫键连接的两嵌段共聚物的新方法.以可逆加成-断裂链转移自由基聚合(RAFT)制备聚苯乙烯大分子链转移剂(PS-RAFT),经伯胺还原得到巯基封端的PS(PS-SH).PS-SH与原子转移自由基聚合(ATRP)引发剂2-溴-2-甲基丙酸-2-(2-吡啶基二硫)乙酯发生交换反应,得到含有二硫键的聚苯乙烯大分子ATRP引发剂(PS-S-S-Br).以PS-S-S-Br引发甲基丙烯酸-2-羟基乙酯(HEMA)的ATRP聚合反应,合成了由二硫键连接的两嵌段共聚物PS-S-S-PHEMA.将PS-S-S-PHEMA可在甲醇中自组装形成以PS为核,PHEMA为壳的球形聚合物胶束,为制备新型含二硫键聚合物提供了新的合成方法.Synthesis of diblock copolymers containing disulfides at the junction points was reported. Reversible addition-fragmentation chain transfer（ RAFT） polymerization of styrene was employed to prepare polystyrene marco RAFT agent（ PS-RAFT）. The terminal RAFT agents of PS were reduced to sulfhydryl groups（ PS-SH） in the presence of primary amine,and the atom transfer radical polymerization（ ATRP） macroinitiator（ PS-S-S-ATRP） was prepared by an exchange reaction between PS-SH and an ATRP initiator containing disulfide bonds. PS-S-S-ATRP was used to initiate the polymerization of 2-hydroxyethyl methacrylate（ HEMA）and PS-S-S-PHEMA diblock copolymers with disulfides at the junction points were obtained. The structures and molecular weights of the diblock copolymers were characterized by proton nuclear magnetic resonance（1H NMR） and gel permeation chromatography（ GPC）. Kinetics study of ATRP of HEMA shows the characteristic of living polymerization. In methanol,the diblock copolymer self-assembles into polymeric micelle with PS cores and PHEMA coronae. Transmission electron microscopy and dynamic light scattering were used to study the morphology changes of the micelles after cleavage of the disulfide bonds. The result shows a new methd to prepare block copolymers with disulfide bonds at the junction points. The self-assenbly strecture of the copolymers will have a wide application in drug release and biological imaging techniques.

关 键 词：二硫键 嵌段聚合物 自组装 可逆加成-断裂链转移自由基聚合 原子转移自由基聚合 

分 类 号：O633.3[理学—高分子化学]