Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Small. 2013 Dec 9;9(23):4077-84. doi: 10.1002/smll.201300657. Epub 2013 Jul 4.
The directed self assembly of a 3-miktoarm star terpolymer (polyisoprene-arm-polystyrene-arm-polyferrocenylethylmethylsilane (3μ-ISF)) into a (4.8²) square symmetry Archimedean tiling pattern is described. Bulk samples of 3μ-ISF generate equilibrium columnar (4.8²) tile patterns (symmetry p 4 mm) on annealing, which is preceded by a metastable c 2 mm centered rectangular structure. In contrast, in thin films of 3μ-ISF blended with PS homopolymer, the c 2 mm phase is stable with columns oriented out of plane when the film thickness is below 50 nm. However, the 3μ-ISF/homopolymer blend rapidly forms a p 4 mm symmetry when the film thickness is ∼80 nm, with grain sizes of several μm and excellent order. Defects in the p 4 mm structure are described.
一种 3 臂星型嵌段共聚物（聚异戊二烯臂-聚苯乙烯臂-聚二茂铁基乙基甲基硅烷（3μ-ISF））的定向自组装成（4.8²）正方形对称的阿基米德密铺图案被描述。3μ-ISF 的本体样品在退火时生成平衡柱状（4.8²）瓦片图案（对称 p 4 mm），这之前是亚稳的 c 2 mm 中心矩形结构。相比之下，在与 PS 均聚物共混的 3μ-ISF 的薄膜中，当薄膜厚度低于 50 nm 时，c 2 mm 相稳定，柱体垂直于薄膜平面取向。然而，当薄膜厚度约为 80nm 时，3μ-ISF/均聚物共混物迅速形成 p 4 mm 对称性，晶粒尺寸为数微米，且具有极好的有序性。描述了 p 4 mm 结构中的缺陷。
