Design of Thermoplastic Elastomers with Self-Consistent Mean Field Theory: Radial (ABA)$_n$ and A(BA)$_n$ Miktoarm Architectures

ORAL

Abstract

Two thermoplastic elastomer designs were evaluated using self-consistent mean field theory. The phase diagram of a radial (A$_1$BA$_2$)$_n$ block copolymer was calculated at $ \chi N$ = 40 per arm as a function of composition ($\emph{f}_A$) and asymmetry between the A end-blocks ($\tau = N_{A1}/(N_{A1}+N_{A2})$). Significant deflection of the phase boundaries towards larger $\emph{f}_A$ occurred for asymmetric triblock copolymers ($\tau\approx 0.15$ and $ \tau\approx 0.90$) due to the interplay between bidispersity and chain-pullout of the A-blocks. The phase diagram of an A$_1$(BA$_2$)$_n$ miktoarm star triblock copolymer was also investigated as a function of $\emph{f}_A$ and $\tau$ at $\chi N$ = 40 per A$_1$BA$_2$ unit. Similar deflections in phase boundaries towards higher $\emph{f}_A$ resulted.

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Authors

  • Nathaniel Lynd

    • UCSB - MC CAM
    • Department of Chemical Engineering and the Materials Research Laboratory, University of California, Santa Barbara

  • Folusho Oyerokun

    • Department of Chemical Engineering and the Materials Research Laboratory, University of California, Santa Barbara

  • Donal O'Donoghue

    • Department of Chemical Engineering and the Materials Research Laboratory, University of California, Santa Barbara

  • Dale Handlin

  • Glenn Fredrickson

    • UCSB - MC CAM
    • Materials Research Laboratory, University of California, Santa Barbara
    • University of California, Santa Barbara
    • Materials Research Lab, UCSB
    • Department of Chemical Engineering and the Materials Research Laboratory, University of California, Santa Barbara
    • UCSB, USA
    • UC Santa Barbara
    • UCSB