Electrostatic Manipulation of Triblock Terpolymer Nanofilm Compartmentalization during Aqueous Photoinitiated Polymerization-Induced Self-Assembly
Electrostatic Manipulation of Triblock Terpolymer Nanofilm Compartmentalization during Aqueous Photoinitiated Polymerization-Induced Self-Assembly
复制标题
水相光引发聚合诱导自组装过程中三嵌段三元聚合物纳米膜区室化的静电操作
DOI：
10.1021/acs.macromol.0c00024
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发表时间：
2020-03-24
期刊：
影响因子：
5.5
通讯作者：
Cai, Yuanli
中科院分区：
文献类型：
--
作者：
Cao, Lei;Zhao, Qingqing;Cai, Yuanli
在25℃下，利用阳离子-中性两嵌段共聚物大分子链转移剂(Macro-CTA)，通过可见光引发双丙酮丙烯酰胺单体的可逆加成-断裂链转移水分散聚合，实现了三嵌段共聚物纳米膜区隔的静电操纵。这种光引发聚合诱导自组装(PhotoPISA)随溶液pH的不同而演化为两种模式。在pH值为2.5时，这种大分子CTA以完全的阳离子嵌段溶解在水中；静电斥力导致传统的水相PISA和单层胶体纳米膜的形成。在pH为7.3时，阳离子链段转变为具有10%阳离子重复单元的疏水离聚体链段，共聚链自组装成弱阳离子胶束，从而导致种子光PISA在疏水片层框架内形成离散的纳米团簇，形成多分隔的单分子层纳米膜。可以通过ABC/BAC嵌段顺序、生长嵌段的聚合度和共聚物浓度来调节纳米级相分离的2D限制纳米团簇和层状结构。这种静电操作为合理设计和制备多室嵌段共聚物2D纳米对象提供了新的思路。
Electrostatic manipulation of triblock terpolymer nanofilm compartmentalization has been achieved via visible light-initiated reversible addition-fragmentation chain transfer aqueous dispersion polymerization of diacetone acrylamide monomer using cationic-neutral diblock copolymer macro-chain transfer agent (macro-CTA) at 25 degrees C. This photoinitiated polymerization-induced self-assembly (photo-PISA) evolves into two modes depending on solution pH. At pH 2.5, this macro-CTA dissolves in water with a fully cationic block; electrostatic repulsion leads to conventional aqueous photo-PISA and the formation of monolayer colloidal nanofilms. At pH 7.3, the cationic block transforms to a hydrophobic ionomer block with 10% cationic repeat units, and the copolymer chains self-assemble into weakly cationic micelles, which leads to seeded photo-PISA via self-assembly into discrete nanoclusters within the hydrophobic lamellar framework to form multicompartmentalized monolayer nanofilms. The nanoscale phase-separated 2D-confined nanoclusters and the lamellar structure can be tuned by the ABC/BAC block sequence, the degree of polymerization of the growing block, and the copolymer concentration. This electrostatic manipulation sheds new light on the rational design and preparation of multicompartmentalized block copolymer 2D nanoobjects.