Carvalho A J F, Pereira-da-Silva M A, Faria R M
Instituto de Fisica de São Carlos, Universidade de São Paulo, C.P. 369, 13560-970, São Carlos, SP, Brazil.
Eur Phys J E Soft Matter. 2006 Jul;20(3):309-15. doi: 10.1140/epje/i2006-10021-5. Epub 2006 Jul 25.
Self-organized block copolymer structures derived from dewetting of thin films are becoming important in nanotechnology because of the various spontaneous and regular sub-micrometric surface patterns that may be obtained. Here, we report on the self-organization of a poly(styrene)-b-poly(ethene-co-butene-1)-b-poly(styrene) triblock copolymer during drying of its solution over a mica substrate. Regular submicrometric arrangements with long-range order were formed at critical polymer concentrations, consisting of parallel ribbons and hexagonal arrays of dots (droplets). This variety of highly ordered structures is explained by the interplay between forming mechanisms, mainly due to "fingering instabilities" at the three-phase line of the copolymer solution during drying. The thickness of the structures was "quantized" due to the microphase separation of the block copolymer. The formation of hexagonal patterns may be attributed to Marangoni instability at the liquid film surface prior to dewetting.
由于可以获得各种自发且规则的亚微米级表面图案，由薄膜去湿衍生出的自组装嵌段共聚物结构在纳米技术中变得越来越重要。在此，我们报道了一种聚（苯乙烯）-b-聚（乙烯-共-丁烯-1）-b-聚（苯乙烯）三嵌段共聚物在云母基底上溶液干燥过程中的自组装情况。在临界聚合物浓度下形成了具有长程有序的规则亚微米级排列，由平行条带和点状（液滴）六边形阵列组成。这种多样的高度有序结构是由形成机制之间的相互作用所解释的，主要是由于干燥过程中共聚物溶液三相线处的“指进不稳定性”。由于嵌段共聚物的微相分离，结构的厚度被“量化”。六边形图案的形成可能归因于去湿前液膜表面的马兰戈尼不稳定性。
