Block copolymers derived from methylcellulose

ORAL

Abstract

Methylcellulose (MC), a cellulose ether derivative, attracts interest in both industry and academia for its unique rheological properties in water. At an average degree of methoxy substitution of 1.8, MC shows a concentration-dependent lower critical solution temperature (LCST) near 45 – 60 °C, above which the solution gels by forming fibrils with a diameter of 15 nm. This diameter is independent of molecular weight, MC concentration, and temperature of formation. Our group has recently showed that room temperature MC chain stiffness can be increased, and fibril formation suppressed, by grafting short to medium length poly(ethylene glycol) (PEG) chains along the MC backbone. In this work we present block copolymers of MC with PEG. Using a selective chemistry, the reducing end-groups of MC are successfully modified into allyl groups. Allylated MC chains are then reacted with hemitelechelic thiol-terminated PEG via photoinitiated thiol-ene click chemistry to form AB type block copolymers. The influence of the PEG block on MC fiber formation is studied as a function of temperature using small angle X-ray scattering and small amplitude oscillatory shear.

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Presenters

  • S. Piril Ertem

    Department of Chemistry, University of Minnesota, Twin Cities, Chemistry, University of Minnesota, University of Minnesota, Department of Chemistry, University of Minnesota

Authors

  • S. Piril Ertem

    Department of Chemistry, University of Minnesota, Twin Cities, Chemistry, University of Minnesota, University of Minnesota, Department of Chemistry, University of Minnesota

  • Svetlana Morozova

    Department of Chemistry, University of Minnesota, Twin Cities, Chemistry, University of Minnesota, University of Minnesota, Department of Chemistry, University of Minnesota

  • Peter Schmidt

    Department of Chemical Engineering and Materials Science, University of Minnesota, Twin Cities, Chemical Engineering and Material Science, University of Minnesota, University of Minnesota, Department of Chemical Engineering and Materials Science, University of Minnesota

  • McKenzie Coughlin

    Department of Chemical Engineering and Materials Science, University of Minnesota, Twin Cities, Chemical Engineering and Material Science, University of Minnesota, University of Minnesota

  • Theresa M. Reineke

    Department of Chemistry, University of Minnesota, Twin Cities, Chemistry, University of Minnesota, University of Minnesota, Department of Chemistry, University of Minnesota

  • Frank Bates

    Department of Chemical Engineering & Materials Science, University of Minnesota, Chemical Engineering and Materials Science, University of Minnesota, Department of Chemical Engineering and Materials Science, University of Minnesota, Twin Cities, University of Minnesota, University of Minnesota - Twin Cities, Chemical Engineering and Material Science, University of Minnesota, Department of Chemical Engineering and Materials Science, University of Minnesota

  • Timothy Lodge

    University of Minnesota, Department of Chemistry, University of Minnesota, Twin Cities, University of Minnesota - Twin Cities, Chemistry, University of Minnesota, Department of Chemistry, University of Minnesota