Influence of deep eutectic solvent on structure and behaviour of wood based cellulose fibres

Deep eutectic solvent (DES) composed of choline chloride and urea can be used as a swelling agent and rheological modifier for wood based cellulose fibres. It has been shown that this particular mixture has an ability to disperse pulp fibres, and the formation of a gel-like suspension takes place. Therefore, as we have previously demonstrated, the utilization of DES enables fibre yarn manufacturing directly from dried pulp without altering the original crystalline structure of cellulose I. In this study the influence of DES on cellulose fibre structure, surface morphology and swelling behaviour was examined in more detail using surface sensitive methods like QCM-D and AFM. According to the preliminary tests, cellulose dissolution was not taking place, which indicates that swelling of the fibres may facilitate the yarn formation by chemically fusing the fibres together. These findings are relevant for efficient utilization of novel solvent systems for cellulosic materials to be exploited for example in composite and textile applications.