Preparation of Multi-chambered Vesicles by Polymerization-induced Self-assembly and the Influence of Solvophilic Fragments in the Core-forming Blocks

Abstract

张文建 a,c 洪春雁 * ,a ( a 中国科学技术大学 高分子科学与工程系 合肥 230026) ( b 安徽大学 化学化工学院 合肥 230601) ( c 安徽大学 物质科学与信息技术研究院 合肥 230601) 摘要 聚合物纳米材料的形貌对于其性能具有重要的影响, 其中囊泡(特别是多腔室囊泡)由于其具备空心结构备受关 注. 聚合诱导自组装(PISA)是一种高效的制备聚合物纳米材料的方法. 然而, 目前利用 PISA 高效制备多腔室囊泡的报 道则相对较少. 本工作中, 以聚乙二醇为大分子可逆加成-断裂链转移(RAFT)试剂(PEG 45 -PETTC)调控苯乙烯(St)在混 合溶剂乙醇/水(质量比 7/3)中的 RAFT 聚合诱导自组装, 成功制备了多腔室囊泡. 同时开展了 St 和寡聚乙二醇甲醚甲基 丙烯酸酯(OEGMA)的 RAFT 共聚合诱导自组装, 探索在成核链段中引入亲溶剂基元 OEGMA 对所得纳米材料形貌的影 响. 由于聚苯乙烯的链刚性较强, 在聚苯乙烯链段中引入亲溶剂链段来增加成核链段的柔顺性是一种已报道的促进形 貌转变的方法. 然而 St 和 OEGMA 在混合溶剂乙醇/水(质量比 7/3)的聚合诱导自组装体系中, 发现亲溶剂基元

Fabrication of multi-compartmental vesicles via RAFT method in polymerization-induced self-assembly

“…In our previous PISA literatures using styrene (St) as the monomer, the monomer conversion is usually low (the rigid polystyrene core makes it difficult for the monomer to diffuse into the micellar core) and the transformation of spherical micelles to other higher-order morphologies is also limited. To get over the morphological transition's restrictions, we employed two techniques, (1) excess styrene was used as the monomer in the polymerization system to plasticize the core-forming blocks (excess styrene monomer swells the core after micelle formation) [3,17]; (2) to introducing solvophilic moieties into the core-forming blocks by copolymerizing with other monomers [17,19]. In this paper, the above two strategies were both not used, but the conversion of styrene got as high as 87.8%, vesicles and even multi-chambered vesicles were obtained.…”

“…Polymeric nanomaterials had already sparked considerable interest because of their prospective uses in a wide range of sectors, including medication delivery, sensors, nano reactors, and catalytic supports [1,2]. Polymerization-induced self-assembly (PISA), which is developed in the last decade, has been demonstrated to be an efficient method for preparing polymeric nanomaterials [3,4]. Polymerizationinduced self-assembly (PISA) combines the synthesis of block copolymers and the self-assembly of block copolymers into one step, which effectively simplifies the preparation process of polymeric nanomaterials, and allows fabricating polymeric nanomaterials at high concentrations (solid content 10~50%).…”

“…However, the majority of the published PISA literature was founded on RAFT polymerization, which may be attributed to RAFT polymerization's good resistance to different active monomers and solutions. [3][4][5][6][7][8][9][10][11][12][13][14].…”