Surface Segregation of Small Macrocyclic

ORAL

Abstract

Surface segregation of the thin film blends containing 20wt{\%} 2k macrocyclic polystyrene were studied using surface MALDI-ToF mass spectrometry (MS), time of flight secondary ion mass spectrometry (ToF-SIMS), and neutron reflectometry (NR). To provide contrast between the species for these techniques, the linear polymer in the blend was deuterated. MALDI-ToF MS results show that the 2k macrocyclic chains are depleted from the surface after a film of an isotopic macrocylic/linear blend (h-CPS2K/ d-LPS2K) is annealed at 125$^{\circ}$C for 12hrs. The surface concentration of CPS is less than 1wt{\%}, while the surface concentration of the hydrogenous component in an analogous h-LPS2K/ d-LPS2K film is 20wt{\%} after annealing. The isotopic effect is not significant for the 2k blends and the architecture effect determines the surface segregation. ToF-SIMS and NR results corroborate this view.

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Authors

  • Shih-Fan Wang

    • Dept. of Polymer Science, The University of Akron, Akron OH 44325-3909
    • The University of Akron, Department of Polymer Science

  • Xiaopeng Li

    • The University of Akron, Department of Chemistry

  • Renfeng Hu

    • Colorado School of Mines, Department of Chemical Engineering

  • Bulent Akgun

    • NIST Center for Neutron Research, NIST, Gaithersburg, MD 20899
    • NCNR, NIST
    • National Institute of Standards and Technology

  • Rebecca Agapov

    • The University of Akron, Department of Polymer Science
    • The University of Akron, Dept. of Polymer Science, Akron, OH

  • Chrys Wesdemiotis

    • The University of Akron, Department of Polymer Science

  • David T. Wu

    • Colorado School of Mines, Department of Chemical Engineering

  • Mark Foster

    • The University of Akron, Department of Polymer Science
    • The University of Akron, Dept. of Polymer Science, Akron, OH