Spinning and Additive Manufacture for Multiscale Cellulose Structures on Textiles and 3D Printed Materials

We use dry-jet wet spinning in a coaxial configuration by extruding an aqueous colloidal suspension of oxidized nanocellulose (hydrogel shell) TOCNF combined with airflow in the core. The coagulation of the hydrogel in a water bath result in hollow filaments (HF) that are drawn continuously at relatively high rates. Additionally, Blueberries pruning waste or BPw was dissolved in an ionic liquid, 1-ethyl-3- methylimidazolium acetate ([emim][OAc]) and regenerated into ligno- cellulose filaments with highly aligned nanofibrils (wide-angle X-ray scattering) that simultaneously displayed extensibility (wet strain as high as 39 %). Finally in alkaline conditions we investigate the interplay between cellulose crystallization and aggregation with interfibrillar interactions, shear forces, and the local changes in the medium's acidity. The latter is affected by the CO2 chemisorbed from the surrounding atmosphere, which, combined with shear forces, explain cellulose gelation. Different instrumental techniques are combined to unveil the fundamental factors that limit cellulose gelation and maximize its dissolution in NaOH(aq).

The obtained solutions are then proposed for developing green and environmentally friendly cellulose-based materials at different dimensions, such as filaments (1D), films(2D) and printed meshes (3D).