Ordering of Triblock Copolymer Surfactants by Blending with a Room Temperature Ionic Liquid

ORAL

Abstract

Well-ordered block copolymer morphologies were obtained by blending Pluronic{\textregistered} PEO-PPO-PEO triblock copolymer surfactants with the room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate. The selective association of the ionic liquid with the PEO blocks raises the effective interaction parameter between the PEO and PPO blocks. Therefore, the copolymer/ionic liquid blends form well-ordered microdomains in the melt, whereas the neat copolymers are phase mixed in the melt. The ionic liquid was confirmed to interact with the PEO chains by a depression in the melting point of the PEO crystals with increasing ionic liquid concentration. Wide angle x-ray scattering and polarized optical microscopy also indicate disruption of PEO crystallization in the blends. Infrared spectroscopy also indicates a strong interaction between the PEO blocks and ionic liquid. The formation of well-ordered microdomains is demonstrated by small angle x-ray scattering experiments, which show the appearance of higher order peaks with increasing ionic liquid concentration.

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Authors

  • Daniel Miranda

    University of Massachusetts

  • James Watkins

    University of Massachusetts, Amherst, Polymer Science and Engineering, University of Massachusetts Amherst, University of Massachusetts, UMass Amherst Department of Polymer Science and Engineering

  • Thomas Russell

    University of Massachusetts Amherst, Univ. Massachusetts Amherst, Dept. of Polymer Sci. Eng., University of Massachusetts, Polymer Science and Engineering Department, University of Massachusetts Amherst, Department of Polymer Science and Engineering University of Massachusetts Amherst, University of Massachusetts, Amherst, University of Massuchusetts at Amherst, Department of Polymer Science and Engineering, University of Massachusetts Amherst, University of Massachusetts-Amherst, Department of Polymer Science and Engineering, University of Massachusetts, Amherst, Polymer Science and Engineering Department, University of Massachusetts-Amherst