Production of lignocellulosic hydrogel-filled fibers inspired by plant cell wall through coaxial wet spinning

Abstract

Coaxial wet spinning is a low-cost and scalable process to produce cellulosic absorbent materials replacing energy-demanding methodologies, such as freeze-drying. By this method, hydrogels (core) could be encapsulated in a polymer sheet (shell) by simultaneous extrusion directly into a coagulant bath. The chosen materials are mandatory to define the spun fiber properties, such as mechanical resistance and water absorptivity. The present proposal aims to produce green and sustainable hydrogel-filled fibers through coaxial wet spinning totally formed by components that can be extracted or produced from lignocellulosic biomass. Fiber-filling hydrogel will contain cellulose nanofibrils, lignin, and hemicellulose coated by a nanocomposite sheet made of cellulose derivates (cellulose acetate or methylcellulose) and cellulose nanocrystals. The polymeric coating should contribute to a better spinning processability, while the composition and content of both the hydrogel and sheet will enable the modulation of the spun fiber properties. These materials are suitable for application as absorbent materials in health care and biomedical area. The process will be optimized based on the morphological, mechanical, and absorption properties of the spun fibers. Rheology measurements and experiments in a quartz crystal microbalance with dissipation monitoring will provide a fundamental comprehension of the molecular interaction of the plant cell-wall components. The results will unveil molecular interactions between hydrogel components and advance in the production of new renewable advanced materials inspired by the plant cell-wall native structure. (AU)