Reinforced magnetic cellulose fiber from ionic liquid solution

Abstract

Composite fibers were prepared by homogeneous dispersion of nanomagnetite (NM) in the ionic liquid 1-ethyl-3-methylimidazolium acetate ([C 2 mim]OAc) using ultrasonication followed by dissolution of microcrystalline cellulose at 90°C and dry-jet wet spinning into a water coagulation bath. The processing method with specific successive steps regarding the addition of the components has a large influence on the quality of dispersion and thus the mechanical properties of the fibers. A nanomagnetite load of up to 0.75% (mass ratio expressed in percent of nanomagnetite to cellulose) in the cellulose matrix results in significantly improved mechanical properties of the fibers, while at loads higher than 1% NM, the ultimate stress and modulus of the fibers are lower because of the formation of large agglomerates that create defects within the fibers. Fibers with uniform diameter and better reproducibility of mechanical properties can be produced utilizing high-performance equipment for fiber processing.