title: Orienting block copolymer microdomains with block copolymer brushes.
abstract: A simple, rapid, and robust technique for controlling the self-assembly of block copolymers (BCPs) with a large segmental interaction parameter, χ, is described using a surface modified with anchored BCP brushes. End-functionalized poly(styrene-b-ethylene oxide)s (PS-b-PEOs), where the fraction of PS (f(PS)) was varied, end-functionalized neat PS, and end-functionalized neat PEO were end-grafted onto Si substrates modifying the surface with polymer brushes. Thin films of cylinder-forming PS-b-PEO were prepared on modified Si substrates and thermally annealed. When neat PS and PEO were used as the anchored brushes, the microdomains of the PS-b-PEO oriented parallel to the substrate upon thermal annealing due to the preferential interactions of one block to the anchored brushes. However, when end-functionalized PS-b-PEOs were used to modify the substrate, hexagonally packed cylindrical PEO microdomains oriented normal to the substrate, having long-range lateral ordering, were obtained over a very wide range of f(PS) (0.32 to 0.77).
authors.affiliation: Department of Polymer Science & Engineering, University of Massachusetts, 120 Governors Drive, Amherst, Massachusetts 01003-4530, United States.
authors.forename: Weiyin
authors.initials: W
authors.lastname: Gu
authors.forename: Sung Woo
authors.initials: SW
authors.lastname: Hong
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Russell
mesh_terms: D003460:Crystallization / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances; D011137:Polystyrenes; D011092:Polyethylene Glycols