Temperature-Induced, Reversible Swelling Transitions in Multilayers of a Cationic Triblock Copolymer and a Polyacid

ORAL

Abstract

We demonstrate large-scale, fully-reversible, thermally-induced volumetric changes in layer-by-layer (LbL) electrostatically self-assembled thin films through the incorporation of A-B-A triblock copolymers, where A is a weak polyelectrolyte block, and B is a temperature-responsive block. Multilayers of a micelle-forming A-B-A triblock copolymer were constructed using LbL deposition with a polyanion. The polyanion type and self-assembly pH were critical parameters for constructing functional films of block copolymer micelles (BCMs). When a polycarboxylic acid was used in self-assembly, films assembled at pH $\ge $ 6 showed fully reversible, 3 to 5-fold changes in film thickness in response to temperature cycling between 6 and 20 $^{\circ}$C, enabled by swelling/collapse of the BCM central block.

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Authors

  • Svetlana Sukhishvili

    • Department of Chemistry, Chemical Biology and Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030
    • Department of Chemistry, Chemical Biology and Biomedical Engineering, Stevens Institute of Technology, Hoboken, New Jersey 07030

  • Wui Siew Tan

    • Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139

  • Robert Cohen

    • Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139

  • Michael Rubner

    • Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139