Unidirectional Alignment of Block Copolymer Films Induced by Expansion of a Permeable Elastomer during Solvent Vapor Annealing

作者：Qiang Zhe; Zhang Longhe; Stein Gila E; Cavicchi Kevin A^*; Vogt Bryan D

来源：Macromolecules, 2014, 47(3): 1109-1116.

DOI：10.1021/ma402131j

One challenge associated with the utilization of block copolymers in nanotechnology is the difficulties associated with alignment and orientation of the self-assembled nanostructure on macroscopic length scales. Here we demonstrate a simple method to generate unidirectional alignment of the cylindrical domains of polystyrene-block-polyisoprene-block-polystyrene, SIS, based on a modification of the commonly utilized solvent vapor annealing (SVA) process. In this modification, cross-linked poly(dimethylsiloxane) (PDMS) is physically adhered to the SIS film during SVA; differential swelling of the PDMS and SIS produces a shear force to align the ordered domains of SIS in the areas covered by PDMS. This method is termed solvent vapor annealing with soft shear (SVA-SS). The alignment direction can be readily controlled by the shape and placement of the PDMS with the alignment angle equal to the diagonal across the rectangular PDMS pad due to a propagating deswelling front from directional drying of the PDMS by a dry air stream. Herman%26apos;s (second order) orientational parameter, S, can quantify the quality of the alignment over large areas with S %26gt; 0.94 obtainable using SVA-SS.

• 出版日期2014-2-11