电场诱导二嵌段共聚物自组装的分子动力学模拟

Molecular dynamics simulation of electric-field-induced self-assembly of diblock copolymers.

作者信息

Zhang Qiuzhi, Xu Rui, Kan Di, He Xuehao

机构信息

Department of Chemistry, School of Science, Tianjin University, and Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China.

出版信息

J Chem Phys. 2016 Jun 21;144(23):234901. doi: 10.1063/1.4953689.

DOI:10.1063/1.4953689

PMID:27334188

Abstract

The self-assembly of block copolymers under an external electric field was studied with a coarse-grained polarizable model that hybridizes the conventional polymeric coarse-grained model and Drude oscillator. The polarizability of the coarse-grained polymeric segment was reflected by the Drude oscillator. Applying this model, the alignment of the lamellar phase of the block copolymer melt under an external electric field was observed and the dynamic coupling information between chain polarization and interface orientation induced by the external electric field was obtained. It is demonstrated that the alignment of the lamellar structure along the electric field direction results from the polarizability difference of the polymer components. Finally, the transitions of phase structures of the block copolymer under an external electric field, from spherical phase to cylindrical phase, from gyroid structure to cylindrical phase, and from gyroid structure to lamellae phase were simulated. The specific evolution pathways were shown.

摘要

利用一种粗粒度可极化模型研究了嵌段共聚物在外部电场作用下的自组装行为，该模型将传统的聚合物粗粒度模型与德鲁德振子相结合。德鲁德振子反映了粗粒度聚合物链段的极化率。应用该模型，观察了嵌段共聚物熔体层状相在外部电场作用下的取向，并获得了外部电场诱导的链极化与界面取向之间的动态耦合信息。结果表明，层状结构沿电场方向的取向是由聚合物组分的极化率差异引起的。最后，模拟了嵌段共聚物在外部电场作用下相结构的转变，包括从球形相到柱状相、从螺旋状结构到柱状相以及从螺旋状结构到层状相的转变。展示了具体的演化路径。