Localizing graphene at the interface of cocontinuous polymer blends: Morphology, rheology, and conductivity of cocontinuous conductive polymer composites

Lian Bai, Siyao He, John W. Fruehwirth, Andreas Stein, Christopher W. Macosko, Xiang Cheng

Research output: Contribution to journalArticle

50 Scopus citations

Abstract

Interfacial localization of graphene in cocontinuous polymer blends is shown to be effective in stabilizing the cocontinuous morphology and increasing conductivity with a low electrical percolation threshold. We created polylactic acid (PLA) and polystyrene (PS) cocontinuous blends filled with thermally reduced graphene oxide (r-GO) localized at the interface. The resulting conductive composites show dramatically improved conductivity at low filler loadings and an ultralow percolation threshold of 0.028 vol. %. We systematically studied the changes of conductivity and rheology of the PLA-PS composites during annealing. We found that r-GO transfers from the PLA phase to the interface during melt compounding and annealing and forms a spanning 3D network, which effectively suppresses the coarsening of the cocontinuous structure. Our study demonstrated that the 3D r-GO network significantly increases the conductivity and the storage modulus of the melt blends. Finally, we constructed a simple model, which quantitatively explains the correlations between structural, electrical, and rheological properties of conductive polymer composites.

Original languageEnglish (US)
Pages (from-to)575-587
Number of pages13
JournalJournal of Rheology
Volume61
Issue number4
DOIs
StatePublished - Jul 1 2017

How much support was provided by MRSEC?

  • Shared

Reporting period for MRSEC

  • Period 4

Fingerprint Dive into the research topics of 'Localizing graphene at the interface of cocontinuous polymer blends: Morphology, rheology, and conductivity of cocontinuous conductive polymer composites'. Together they form a unique fingerprint.

  • Projects

    MRSEC SEED Projects

    11/1/14 → …

    Project: Research project

    University of Minnesota MRSEC (DMR-1420013)

    Lodge, T. P.

    11/1/1410/31/20

    Project: Research project

    Cite this