Structure of Block Copolymer Hydrogel Formed by Complex Coacervate Process

ORAL

Abstract

Complex coacervation occurs when oppositely charged polyelectrolytes associate in solution, forming dense micron-sized droplets. Hydrogels with coacervate block domains were formed by mixing two ABA and A'BA' triblock copolymer solutions in water where the A and A' blocks are oppositely charged. Small-angle neutron scattering (SANS) was used to investigate the structure of hydrogels formed by ABA triblock copolymers (A block: poly(allyl glycidyl ether) functionalized with guanidinium (A) or sulfonate (A'), B block: poly(ethylene oxide)). By using an appropriate fitting model, structural information such as coacervate core block radius and water volume fraction w can be extracted from SANS data. The results reveal that w in the coacervate core block was significantly higher than in conventional triblock copolymer hydrogels where microphase separation is driven by the hydrophobicity of the core-forming blocks.

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Authors

  • SooHyung Choi

    University of California, Santa Barbara, University of Minnesota

  • Julia Ortony

    University of California, Santa Barbara

  • Daniel Krogstad

    University of California, Santa Barbara, Materials Research Laboratory, University of California at Santa Barbara

  • Jason Spruell

    University of California, Santa Barbara

  • Nathaniel Lynd

    University of California, Santa Barbara, University of California Santa Barbara

  • Songi Han

    University of California, Santa Barbara

  • Edward J. Kramer

    University of California, Santa Barbara, Departments of Materials and Chemical Engineering, UCSB, 93106-5050, Departments of Materials and Chemical Engineering, UCSB, Materials Research Laboratory, UCSB, University of California Santa Barbara, University of California - Santa Barbara