Dry-jet wet electrospinning of native cellulose microfibers with macroporous structures from ionic liquids

In this study, we have provided a review of electrospun cellulose micro/nanofibers from ionic liquids (ILs) and cosolvents from which we identify a lack of previous studies focusing on the structural morphology of the dry-jet wet electrospun native cellulose fibers from ILs. We have therefore aimed to investigate factors influencing the structural morphology of cellulose/IL electrospun fibers and investigate the coagulation parameters on this morphology. The electrospinning of 10% w/v cellulose/([C2MIM][OAc]/MIM) (1/1, v/v) solution was shown to produce macroporous fibers with average diameters of 2.8 +/- 1.4 mu m with pore sizes from 100 to 200 nm. We have found that coagulation bath type and immersion time affect the morphological structure of the electrospun fibers. The fiber spinnability, formation, and morphological structure are mainly dependent on the method used to collect and coagulate/solidify the fibers. The physical properties of the dissolved cellulose were measured and these are discussed in terms of the solution spinnability. The structural morphology of the electrospun cellulose fibers was characterized by scanning electron microscopy, and finally the extraction of IL from the fiber body was confirmed by nuclear magnetic resonance. The electrospun cellulose fibers morphology shows the formation of both micron and nanometer sized fibers with different morphological "macroporous" structures. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47153.