Song Yongbing, Jiang Run, Wang Zheng, Yin Yuhua, Li Baohui, Shi An-Chang
School of Physics, Nankai University, Tianjin 300071, China.
Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada.
ACS Omega. 2020 Apr 15;5(16):9366-9376. doi: 10.1021/acsomega.0c00374. eCollection 2020 Apr 28.
The self-assembly of a cyclic AB copolymer system with relatively long A blocks and short B blocks in B-selective solvents is investigated using a simulated annealing method. By investigating the effect of the lengths and solubilities of A and B blocks ( and , ε and ε), the incompatibility between A and B blocks (ε), as well as the polymer concentration ( ) and the conditions for the formation of multicompartment vesicles in cyclic diblock copolymer solutions, is predicted. The phase diagrams in terms of , ε, and are constructed. The mechanism of the morphological transition is elucidated. It is shown that for cyclic copolymers the change in the above factors relating to the polymer and solvent properties all can lead to the transition from simple vesicles to multicompartment vesicles, but two different transition mechanisms are revealed. In addition, our simulations demonstrate that the self-assembly of cyclic copolymers could provide a powerful strategy for regulating the compartment number and the wall thickness of the multicompartment vesicles by adjusting the block solubilities and block lengths, respectively. These findings will facilitate the application of multicompartment architectures in cell mimicry, drug delivery, and nanoreactors.
采用模拟退火方法研究了在B选择性溶剂中具有相对较长A嵌段和较短B嵌段的环状AB共聚物体系的自组装过程。通过研究A和B嵌段的长度和溶解度（ 和 ，ε和ε）、A和B嵌段之间的不相容性（ε）以及聚合物浓度（ ），预测了环状二嵌段共聚物溶液中多隔室囊泡形成的条件。构建了关于 、ε和 的相图。阐明了形态转变的机制。结果表明，对于环状共聚物，上述与聚合物和溶剂性质相关的因素的变化都可导致从简单囊泡向多隔室囊泡的转变，但揭示了两种不同的转变机制。此外，我们的模拟表明，环状共聚物的自组装可以分别通过调节嵌段溶解度和嵌段长度，为调节多隔室囊泡的隔室数量和壁厚提供一种有力策略。这些发现将促进多隔室结构在细胞模拟、药物递送和纳米反应器中的应用。
