PEG接枝大分子RAFT试剂的设计及其对无皂乳液RAFT聚合嵌段共聚物胶体结构的影响

项目名称： PEG接枝大分子RAFT试剂的设计及其对无皂乳液RAFT聚合嵌段共聚物胶体结构的影响

项目编号： No.21274066

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 张望清

作者单位： 南开大学

项目金额： 83万元

中文摘要： 本项目的研究目标，是通过大分子RAFT试剂（Macro-RAFT试剂）的设计，实现可控的无皂乳液RAFT聚合反应，制备浓度高、稳定性好、结构可调节的嵌段共聚物胶体。为此，合成亲/疏水性质和空间位阻可调节的聚乙二醇（PEG）接枝共聚物Macro-RAFT试剂，应用于苯乙烯或丙烯酸酯无皂乳液RAFT聚合。在无皂乳液RAFT聚合条件下，随着单体转化率增加，嵌段共聚物分子量Mn发生可控的增长，嵌段共聚物胶体的尺寸和形态发生规律性变化。PEG接枝Macro-RAFT试剂的结构，为实现可控的无皂乳液RAFT聚合和嵌段共聚物胶体结构的演变提供了可能。本项目旨在通过对Macro-RAFT试剂的结构对无皂乳液RAFT聚合的影响的研究，揭示嵌段共聚物的Mn和分子量分布系数PDI随单体转化的变化规律，揭示嵌段共聚物胶体的尺寸和形态的演变规律，探索出一条制备浓度高、稳定性好、结构可调节的嵌段共聚物胶体的有效方法。

中文关键词： 乳液RAFT聚合；胶体；大分子RAFT试剂；分散RAFT聚合；嵌段共聚物

英文摘要： The proposed project is focused on the macro-RAFT agent mediated with surfactant-free emulsion RAFT polymerization of styrene or acrylate and the structure evolution of the in situ synthesized block copolymer colloids. To get well-controlled surfactant-free emulsion RAFT polymerization and to achieve controlled evolution of the in situ synthesized block copolymer colloids, a special macro-RAFT agent of poly(ethylene glycol) grafted amphiphilic copolymer is employed. This macro-RAFT agent of the poly(ethylene glycol) grafted amphiphilic copolymer has three characters. First, it contains a terminal of the trithiocarbonate reactive group, which makes it suitable in the surfactant-free emulsion RAFT polymerization. Second, the macro-RAFT agent contains a hydrophobic polymer segment and a hydrophilic PEG-graft segment, and the hydrophilic/hydrophobic balance (HLB) of the macro-RAFT agent can be tuned. Third, the strong steric repulsion due to the densely grafted PEG brushes exists in the macro-RAFT agent. All the three characters make the macro-RAFT agent to be the suitable candidate for the surfactant-free emulsion RAFT polymerization of styrene or acrylate. Besides, the in situ synthesized colloids of block copolymer are expected to change their size and morphology with the increase in the monomer conversion, which

英文关键词： Emulsion RAFT polymerization；colloids；macro-RAFT agent；dispersion RAFT polymerization；block copolymer