Phase Behavior of Sphere-Forming Triblock Copolymers in Films

Hong-Ge Tan, Qing-Gong Song, Xin-Huan Yang, Ya-Jing Deng

College of Science, Civil Aviation University of China, Tianjin, China.
College of Science, Hebei University of Technology, Tianjin, China.

DOI: 10.4236/ojapps.2012.23023                

Abstract

The self-assembly of sphere-forming triblock copolymers confined between two thin homogeneous surfaces is investigated based on mean-field dynamic density functional theory. The morphologies deviating from the bulk sphere-forming phase are revealed, including cylinders oriented perpendicular to the surface, cylinders oriented parallel to the surface, perforated lamellae and lamellae by varying film thickness and surface field strength. The phase diagram of surface reconstruction is also constructed. By comparing the present phase diagram with the other relevant phase diagram for the cylinder-forming triblock copolymer film, the difference between the sphere-forming and the cylinder-forming triblock copolymer thin film is discussed.

Keywords

Triblock Copolymer; Mean-Field Dynamic Density Functional Theory; Thin Film

Conflicts of Interest

The authors declare no conflicts of interest.

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