Pinna Marco, Diaz Javier, Denison Christopher, Zvelindovsky Andrei, Pagonabarraga Ignacio
School of Mathematics and Physics, College of Health and Science, Centre for Computational Physics, University of Lincoln, Brayford Pool, Lincoln, LN6 7TS, UK.
Departament de Física de la Matèria Condensada, Universitat de Barcelona, Martí i Franqués 1, 08028 Barcelona, Spain.
Soft Matter. 2025 Jan 15;21(3):476-487. doi: 10.1039/d4sm01241k.
The potential applications of block copolymer thin films, utilising their self-assembly capabilities, are enhanced when achieving long-range ordering. In this study we explain the experimental alignment of lamellae under shear flow findings [S. Pujari , 2012, , 5258] and classify the alignment mechanisms based on shear rate and segregation, uncovering similarities to the systems subjected to electric fields, suggesting a common pathway of lamellae orientations. However, the presence of thin films surfaces introduces distinct features in the lamellae orientation under shear compared to electric fields. Notably, we observe the emergence of a three-dimensional rotation alongside the conventional two-dimensional rotation. Furthermore, a transient regime has been identified within the melting mechanism, which confirms the existence of the checkboard pattern proposed by Schneider [, 2018, , 4642]. These findings significantly enhance our understanding of block copolymer alignments and shed light on the intricate interplay between external fields and the lamellar structure.
利用嵌段共聚物薄膜的自组装能力，当实现长程有序时，其潜在应用会得到增强。在本研究中，我们解释了层状结构在剪切流作用下的实验取向结果[S. Pujari, 2012, , 5258]，并基于剪切速率和相分离对取向机制进行分类，发现其与受电场作用的体系存在相似性，这表明层状结构的取向存在一条共同路径。然而，与电场相比，薄膜表面的存在在剪切作用下层状结构的取向中引入了不同的特征。值得注意的是，我们观察到除了传统的二维旋转外，还出现了三维旋转。此外，在熔化机制中确定了一个瞬态区域，这证实了Schneider [, 2018, , 4642]提出的棋盘图案的存在。这些发现显著增进了我们对嵌段共聚物取向的理解，并揭示了外部场与层状结构之间复杂的相互作用。
