Magnetic field effects on cellulose nanocrystal ordering in a non-aqueous solvent
- PDF / 2,730,316 Bytes
- 10 Pages / 547.087 x 737.008 pts Page_size
- 50 Downloads / 155 Views
(0123456789().,-volV) ( 01234567 89().,-volV)
ORIGINAL RESEARCH
Magnetic field effects on cellulose nanocrystal ordering in a non-aqueous solvent Amira Barhoumi Meddeb . Inseok Chae . Aijie Han . Seong H. Kim . Zoubeida Ounaies
Received: 18 February 2020 / Accepted: 25 June 2020 Ó Springer Nature B.V. 2020
Abstract Cellulose nanocrystals (CNCs) are rodshaped particles that can self-assemble into a chiral nematic phase at certain contents. Due to their negative diamagnetic susceptibility and high aspect ratio, the structure of the chiral nematic phase of CNC suspensions can be manipulated using a magnetic field, which is a promising path to extending local order to a larger scale. The ability to manipulate CNCs in non-aqueous solvents is critically needed to incorporate them in a wide range of polymers. So far, magnetic field-induced manipulation of CNCs in Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10570-020-03320-5) contains supplementary material, which is available to authorized users. A. Barhoumi Meddeb Z. Ounaies (&) Department of Mechanical Engineering, The Pennsylvania State University, University Park, PA 16802, USA e-mail: [email protected] A. Barhoumi Meddeb I. Chae S. H. Kim Z. Ounaies Materials Research Institute, The Pennsylvania State University, University Park, PA 16802, USA
suspension was reported for aqueous suspensions only, whereas a much-needed similar study for nonaqueous solvents has not been reported to the best of our knowledge. In this paper, we investigate the CNC ordering in n-methylformamide (NMF) under a 0.7 T magnetic field and compare it to the order achieved in H2O. The formation of a well-defined chiral nematic phase and its viscosity have a significant influence on the rate and extent of the field-induced orientation of CNCs. A clearly formed chiral nematic phase has a high potential for increased levels of field-induced ordering. And the chiral nematic phase with the lowest viscosity showed the largest increase in ordering when the magnetic field is applied before reaching equilibrium and plateauing. In contrast, the higher viscosity suspensions exhibited limited temporal changes after the initial field effect. These findings will facilitate the fabrication of globally ordered CNCs in a variety of polymers under a magnetic field, which is a necessary step to expanding the engineering applications of large-scale cellulose-based composites with anisotropic properties.
I. Chae S. H. Kim Department of Chemical Engineering, The Pennsylvania State University, University Park, PA 16802, USA A. Han Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802, USA
123
Cellulose
Graphic Abstract
Keywords Cellulose nanocrystals Non-aqueous solvent Magnetic field manipulation In-situ smallangle x-ray scattering
Introduction Cellulose nanocrystals (CNCs) have gained increasing attention in the past decades due to the abundance of cellulose as a renewable resource as we
Data Loading...
