Electric-field-induced lamellar to hexagonally perforated lamellar transition in diblock copolymer thin films: kinetic pathways.
Electric-field-induced lamellar to hexagonally perforated lamellar transition in diblock copolymer thin films: kinetic pathways.
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二嵌段共聚物薄膜中电场诱导的层状到六角形穿孔层状转变：动力学途径。
DOI：
10.1039/c6cp04903f
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
B. Nestler
中科院分区：
文献类型：
--
作者：
A. Mukherjee;K. Ankit;A. Reiter;M. Selzer;B. Nestler
迄今为止，众所周知，对称嵌段共聚物在电场和基质亲和力的共同影响下演变成平行、垂直和混合层状形态。在目前的工作中，我们表明，额外施加的限制可以在单层和双层薄膜中实现新型平行层状到六角形穿孔层状（HPL）的转变。使用 Ohta-Kawasaki 泛函进行三维数值研究，并辅以麦克斯韦方程的精确解。 HPL 显示在超薄膜中平行和垂直层状转变之间的相图狭窄区域内以大的基材亲和力稳定。此外，我们还确定穿孔片层是平行到垂直片层转变过程中的中间结构。使用闵可夫斯基泛函进行系统分析可以更深入地了解相关的动力学途径。
Symmetric block-copolymers, hitherto, are well known to evolve into parallel, perpendicular and mixed lamellar morphologies under the concomitant influence of an electric field and substrate affinity. In the present work, we show that an additional imposed confinement can effectuate a novel parallel lamellar to hexagonally perforated lamellar (HPL) transition in monolayer and bilayer films. Three dimensional numerical studies are performed using the Ohta-Kawasaki functional, complemented with an exact solution of Maxwell's equation. HPL is shown to stabilize at large substrate affinity in a narrow region of the phase diagram between parallel and perpendicular lamellar transitions in ultra-thin films. Additionally, we also identify perforated lamellae as intermediate structures during parallel-to-perpendicular lamellar transition. A systematic analysis using Minkowski functionals yields deeper insights into the associated kinetic pathways.