All-Cellulose Composites of Nanofibril and Molecular Cellulose

POSTER

Abstract

Cellulose nanofibrils (CNFs) are the basic structural elements of most cellulosic materials; they show excellent mechanical characteristics due to a high crystallinity. Molecular solutions of cellulose (MSC) with no apparent aggregation are produced with an ionic liquid and dimethyl sulfoxide (DMSO) binary solvent mixture. Cellulose dissolution occurs by maintaining a 3:1 molar ratio of ionic liquid to cellulose sugar units. The use of DMSO minimizes the amount of ionic liquid used and allows control over viscosity. In this study, all-cellulose nanocomposites of CNFs and regenerated cellulose from MSC have been fabricated by co-precipitation. CNFs with average diameters of 2.5$+$/-0.5 nm and lengths of 300$+$/-100 nm were initially dispersed in water, then suspended in DMSO by solvent exchange and then mixed with MSC. The resultant mixtures were used to cast nanocomposite thin films. The microstructure of the films was studied using optical, atomic force, and electron microscopy which show an even dispersion of CNFs within the regenerated cellulose. Water-uptake behavior was investigated using small angle neutron scattering. The nanocomposite films show higher water resistance compared to neat NFC films and similar to that of cellulose regenerated from MSC.

Authors

  • Doug Henderson

    Department of Materials Science and Engineering, Univerisity of Maryland-College Park, MD

  • Xin Zhang

    Department of Materials Sciene, Univ of Maryland-College Park, MD, Department of Materials Science and Engineering, University of Maryland, College Park, Department of Materials Science and Engineering, Univerisity of Maryland-College Park, MD

  • Yimin Mao

    Department of Materials Science and Engineering, University of Maryland, College Park/NCNR, NIST, NCNR, NIST, Gaithersburg, MD

  • Liangbing Hu

    Department of Materials Science and Engineering, Univerisity of Maryland-College Park, MD

  • Robert Briber

    Department of Materials Sciene, Univ of Maryland-College Park, MD, Department of Materials Science and Engineering, University of Maryland, College Park, Department of Materials Science and Engineering, Univerisity of Maryland-College Park, MD

  • Howard Wang

    Univ of Maryland-College Park, Department of Materials Sciene, Univ of Maryland-College Park, MD, Department of Materials Science and Engineering, University of Maryland, College Park, Department of Materials Science and Engineering, Univerisity of Maryland-College Park, MD