Rich Phase Behavior of Sphere-Forming Asymmetric ABA$^{\mathrm{\prime }}$C Block Copolymer Melts

ORAL

Abstract

Motivated by self-consistent field theory simulations, the effect of ABA$^{\mathrm{\prime }}$ corona block length asymmetry on the phase behavior of ABA$^{\mathrm{\prime }}$C-type tetrablock terpolymers has been examined. The chosen model system, poly(styrene)-$b$-poly(isoprene)-$b$-poly(styrene)-$b$-poly(ethylene oxide) (SIS$^{\mathrm{\prime }}$O), has been characterized using a combination of small-angle X-ray scattering, transmission electron microscopy, and dynamic mechanical spectroscopy. Asymmetric SIS$^{\mathrm{\prime }}$O tetrablocks reveal a rich variety of sphere-forming phases over compositions and molecular weights where symmetric SISO polymers formed only hexagonally oriented cylinders. These include FCC, HCP, and complex symmetries such as the Frank-Kasper $\sigma $ and A15 phases.

*NSF Award 1333669

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Authors

  • Sid Chanpuriya

    • Univ of Minnesota - Twin Cities

  • Akash Arora

    • Univ of Minn - Minneapolis
    • Univ of Minnesota - Twin Cities

  • Kyungtae Kim

    • Univ of Minnesota - Twin Cities

  • Kevin Dorfman

    • University of Minnesota
    • Department of Chemical Engineering and Materials Science, University of Minnesota
    • University of Minnesota - Twin cities
    • University of Minnesota - Minneapolis
    • Dept. Chemical Engineering and Materials Science, University of Minnesota - Twin Cities
    • Univ of Minn - Minneapolis
    • Univ of Minnesota - Twin Cities

  • Frank Bates

    • University of Minnesota, Department of Chemistry and Materials Science
    • University of Minnesota
    • Univ of Minn - Minneapolis
    • Univ of Minnesota - Twin Cities