title: Surface segregation driven by molecular architecture asymmetry in polymer blends.
abstract: The contributions of chain ends and branch points to surface segregation of long-branched chains in blends with linear chains have been studied using neutron reflectometry and surface-enhanced Raman spectroscopy for a series of novel, well-defined polystyrenes. A linear response theory accounting for the number and type of branch points and chain ends is consistent with surface excesses and composition profile decay lengths, and allows the first determination of branch point potentials. Surface excess is determined primarily by chain ends with branch points playing a secondary role.
authors.affiliation: Department of Polymer Science, The University of Akron, Akron, Ohio 44325, USA.
authors.forename: Jae Sik
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Polymer Science, The University of Akron, Akron, Ohio 44325, USA.
authors.forename: Nam-Heui
authors.initials: NH
authors.lastname: Lee
authors.affiliation: Department of Polymer Science, The University of Akron, Akron, Ohio 44325, USA.
authors.forename: Somesh
authors.initials: S
authors.lastname: Peri
authors.affiliation: Department of Polymer Science, The University of Akron, Akron, Ohio 44325, USA.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Foster
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
authors.forename: Charles F
authors.initials: CF
authors.lastname: Majkrzak
authors.affiliation: Department of Chemical Engineering and Department of Chemistry, Colorado School of Mines, Golden, Colorado 80401, USA.
authors.forename: Renfeng
authors.initials: R
authors.lastname: Hu
authors.affiliation: Department of Chemical Engineering and Department of Chemistry, Colorado School of Mines, Golden, Colorado 80401, USA.
authors.forename: David T
authors.initials: DT
authors.lastname: Wu