作者：Jiani Ma, Jie Cui, Yuanyuan Han, Wei Jiang, Yingchun Sun
关键字：Monte Carlo模拟, ABCA四嵌段共聚物, A选择性溶剂, 胶束形貌, Janus结构, 相图
论文来源：期刊
具体来源：RSC Advances, 2015, 5(105), 86473-86484
发表时间：2015年

摘要：采用格子Monte Carlo模拟研究了ABCA四嵌段共聚物在A选择性溶剂中的相行为，重点关注B、C嵌段疏溶剂相互作用（εBS和εCS）对胶束形貌的影响。考虑A2B6C6A2、A2B7C5A2和A2B8C4A2三种四嵌段共聚物，给出了以εCS和B、C嵌段疏溶剂相互作用差（以r=εBS/εCS衡量）为变量的相图。研究发现，r和εCS均可影响胶束的比表面积并导致ABCA四嵌段共聚物胶束形貌变化；r还可改变疏溶剂链构象，进而影响胶束疏溶剂部分的微结构。对于A2B7C5A2和A2B8C4A2四嵌段共聚物，获得了弯曲Janus带和片层、短Janus管以及碗状半囊泡等多种新颖胶束形貌。有趣的是，在这两种四嵌段共聚物的相图中，具有Janus状疏溶剂部分的胶束类型占多数，这主要源于B、C嵌段之间疏溶剂相互作用的平衡。

Abstract：The phase behavior of ABCA tetrablock copolymers in A-selective solvents is investigated using Lattice Monte Carlo simulation, focusing on the effects of the solvophobic interactions of blocks B and C (εBS and εCS) on micelle morphologies. Three kinds of ABCA tetrablock copolymers, i.e., A2B6C6A2, A2B7C5A2 and A2B8C4A2, are considered, and phase diagrams as a function of εCS and the solvophobic interaction difference between blocks B and C (measured by r=εBS/εCS) are given. It is found that r and εCS can both affect the specific surface area of micelles and lead to morphological changes of ABCA tetrablock copolymer micelles. In addition, r can change the solvophobic chain conformation and hence affect the micro-structures of the solvophobic parts of the micelles. For A2B7C5A2 and A2B8C4A2 tetrablock copolymers, several novel micelle morphologies, such as bended Janus ribbon and lamella, short Janus tube, and bowl-shaped semivesicle, are obtained. Interestingly, in the phase diagrams of A2B7C5A2 and A2B8C4A2, the micelle type with Janus-like solvophobic parts is the majority micelle type, which mainly results from the solvophobic interaction balance between blocks B and C.

论文链接：https://doi.org/10.1039/c5ra11865d