Effect of magnetic field alignment of cellulose nanocrystals in starch nanocomposites: Physicochemical and mechanical properties

The magnetic field (MF) induced alignment of cellulose nanocrystals (CNC) within a starch matrix is investigated and its effect on the physicochemical and mechanical properties of the nanocomposites are discussed in the paper. Two different kinds of CNC i.e. plant-CNC and tunicate-CNC and its hybrid combination are studied to understand the effect of aspect ratio of CNC on the properties of nanocomposite. Nanocomposites with tunicate sourced CNC showed higher tensile strength and modulus, and lower water vapor permeability as compared to plant sourced CNC. These properties are higher for nanocomposites prepared under MF. The modulus of starch nanocomposites increased from 0.26 GPa and 0.32 GPa to 0.38 GPa and 0.44 GPa, respectively for plant-CNC and tunicate-CNC when exposed to MF. The improved orientation and alignment of CNC in presence of MF is further supported by Raman and scanning electron micrographs studies.