Shear-dependent structures of microfibrillated cellulose gels
July 21-24, 2019
Cellulosic nanomaterials have recently gained increased attention due to their potential for use as an environmentally friendly replacement conventional materials in many diverse applications. Understanding the rheology of these resources is critical to properly tailor their properties and processing conditions. Aqueous suspensions of microfibrillated cellulose form weak physical gels at low concentrations due to extensive entanglement and hydrogen bonding. These gels are shown to have complex structural properties that are directly dependent on their recent shear history. In this work we discuss the effects of “slow quench” and “fast quench” shear conditions on the suspension properties, including yield stress, viscosity, and structure elasticity. We also assess the recovery of the network structure itself as a function of the applied breakdown conditions. These observations give detailed insight to the morphology of the floc-based network structure and help to quantify critical conditions that characterize the floc dynamics.
Emily Facchine and Saad Khan, "Shear-dependent structures of microfibrillated cellulose gels" in "Colloidal, Macromolecular and Biological Gels II", Samiul Amin, Manhattan College, USA Saad Khan, North Carolina State University, USA Srini Raghavan, University of Maryland College Park, USA Eds, ECI Symposium Series, (2019). https://dc.engconfintl.org/cmb_gels_ii/3