Materials Chemistry Section, Department of Chemistry, University College Cork, College Road, Cork, Ireland.
J Colloid Interface Sci. 2013 Mar 1;393:192-202. doi: 10.1016/j.jcis.2012.10.070. Epub 2012 Nov 15.
The use of random copolymer brushes (polystyrene-r-polymethylmethacrylate--PS-r-PMMA) to 'neutralise' substrate surfaces and ordain perpendicular orientation of the microphase separated lamellae in symmetric polystyrene-b-polymethylmethacrylate (PS-b-PMMA) block copolymers (BCPs) is well known. However, less well known is how the brushes interact with both the substrate and the BCP, and how this might change during thermal processing. A detailed study of changes in these films for different brush and diblock PS-b-PMMA molecular weights is reported here. In general, self-assembly and pattern formation is altered little, and a range of brush molecular weights are seen to be effective. However, on extended anneal times, the microphase separated films can undergo dimension changes and loss of order. This process is not related to any complex microphase separation dynamics but rather a degradation of methacrylate components in the film. The data suggest that care must be taken in interpretation of structural changes in these systems as being due to BCP only effects.
使用无规共聚物刷（聚苯乙烯-聚甲基丙烯酸甲酯 - PS-r-PMMA）来“中和”基底表面，并规定对称聚苯乙烯-嵌段-聚甲基丙烯酸甲酯（PS-b-PMMA）嵌段共聚物（BCP）中微相分离层的垂直取向是众所周知的。然而，不太为人所知的是刷子如何与基底和 BCP 相互作用，以及这种相互作用在热加工过程中如何变化。本文详细研究了不同刷和二嵌段 PS-b-PMMA 分子量的这些薄膜的变化。一般来说，自组装和图案形成变化很小，并且观察到一系列刷分子量是有效的。然而，在长时间退火后，微相分离膜会发生尺寸变化和失序。这个过程与任何复杂的微相分离动力学无关，而是膜中甲基丙烯酸酯成分的降解。数据表明，在解释这些体系中的结构变化时，必须小心谨慎，不要将其归因于 BCP 的影响。
