Water-stable pulp fibre yarns from deep eutectic solvent dope

New method for forming pulp fibre yarns was developed. The method is simple, inexpensive and does not use harmful chemicals. Deep eutectic solvents (DESs) are eutectic mixtures consisting two or more components that together have lower melting point compared to melting points of individual components. DESs have been previously studied with respect to cellulose dissolution, functionalization and pre-treatment. The new method uses the mixture of choline chloride and urea, which is used as swelling and dispersing agent for the pulp fibres in yarn forming process. Choline chloride and urea DES was found not to affect the ultrastructure of pulp or crystalline form of cellulose. Without dissolution and regeneration, original cellulose I structure can be maintained. Polyacrylic acid was used as an additive to enable crosslinking and water stability of the fibre yarn. All the materials are recyclable and reusable in the process