Self-assembly of PS-b-PNIPAM-b-PS block copolymer thin films via selective solvent annealing

POLYMER

卷:107

Article

Mocan, Merve¹  Kamperman, Marleen¹ 

[1] Wageningen Univ, Phys Chem & Soft Matter, Stippeneng 4, NL-6708 WE Wageningen, Netherlands

关键词: Block copolymer self-assembly;    Selective solvent annealing;    Hexagonally ordered perpendicular cylinders;    PS-b-PNIPAM-b-PS block copolymer;   

DOI  :  10.1016/j.polymer.2016.08.033

来源: Elsevier

【 摘 要 】

Block copolymer (BCP) thin films are interesting material systems for nanofabrication since they can form well-defined periodic nanostructures by microphase separation. However, attaining a specific morphology with the required orientation can be challenging. In this study, we investigated the morphological behavior of polystyrene-b-poly(N-isopropylacrylamide)-b-polystyrene (PS-b-PNIPAM-bPS) BCP thin films by using Atomic Force Microscopy (AFM) and in-situ Grazing-Incidence X-ray Scattering (GISAXS) during selective solvent annealing. Thin films of a lamellar BCP were annealed by using various solvents with different selectivity for the blocks, such as PNIPAM-selective methanol, nonselective tetrahydrofuran (THF) and PS-selective toluene. Solvent annealing using methanol: THF 1: 2 (v:v) or methanol: toluene 1: 1 (v: v) resulted in the formation of hexagonally ordered perpendicular cylinders, whereas no sustained long-range order was found when only one type of solvent was used. PS-b-PNIPAM-b-PS BCP thin films that have hexagonally ordered perpendicular cylinders are promising for applications where thermo-responsiveness is desired, such as nanofiltration and biomedical applications. (C) 2016 Elsevier Ltd. All rights reserved.

【 授权许可】

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