Electrospun cellulose fibers from ionic liquid: Practical implications toward robust morphology

Abstract

Fibrous matrix of cellulose was obtained by wet-type electrospinning of cellulose in ionic liquid, 1-butyl-3-methylimidazolium acetate (BMIMAc). The experiments were designed to determine the effects of electric field intensity and the amount of dissolved cellulose on cellulose fiber morphology and diameter. Taking to account practical implications, that is, fiber size and the effectiveness of production, the most effective production of fibers took place using 3% cellulose/BMIMAc solution at electric field of 4.8 kV cm À1 , feed rate of 2.38 ml h À1 . Analysis has shown that cellulose was fully dissolved and consisted purely of regenerated cellulose (type II), while having porosity of 90% and average fiber width of 1.95 ± 0.9 μm. The scanning electron microscopy and micro-computed tomography analyses revealed a robust structural integrity of the formed fibrous matrix, which featured an area density of 85 ± 8 g/ m 2 . The mechanical properties (strength of 12.03 ± 1.1 MPa; strain at break 2.6 ± 0.3%) indicate that in this study strong fibrous cellulose matrix was formed which could be used for the production of biocomposites or as biocompatible scaffolds.

Preparations and Properties of Ionic Liquid-Assisted Electrospun Biodegradable Polymer Fibers

“…In addition, the chemical property, such as the infrared spectrum of the electrospun cellulose fibers showed almost no difference from the spectrum of the virgin cellulose. This indicated that the cellulose retained its original chemical structure, as well as [C 4 mim][OAc] and the washing solvents which were adequately leached from the electrospun cellulose fibers [6]. Nevertheless, the crystalline property, such as the intensity of the X-ray diffraction peak of the electrospun cellulose fibers is significantly decreased, compared to the virgin cellulose (Figure 6a).…”

“…Table 7 shows the properties of electrospun biodegradable polymer fibers were assisted by ionic liquids as solvents. The electrospun cellulose fibers were prepared by Ciuzas et al from raw cellulose fibers using [C 4 mim][OAc] as a solvent [6]. The morphological, chemical, crystalline, and thermal properties of the prepared electrospun fibers were characterized by a scanning electron microscope (SEM), Fourier transform infrared spectrometer, X-ray diffractometer (XRD), and thermal gravimetric analyzer.…”

“…Additionally, the thermal property, such as the decomposition temperature of the electrospun cellulose fibers is lower than that of the virgin cellulose. This implies that the electrospun cellulose fibers have less thermal stability [6]. Therefore, it can be concluded that the use of [C 4 mim][OAc] provides electrospun cellulose fibers with low crystallinity and low thermal stability.…”

“…Currently, ionic liquids are widely utilized in the dissolution and modification of natural and synthetic biodegradable polymers [40,41]. Therefore, the utilization of ionic liquids in the electrospinning of biodegradable polymers is encouraging because ionic liquids have an excellent dissolution ability, negligible vapor pressure, good ionic conductivity, and ease of solvent recovery [2,6,37].…”

Cellulose-based electrospun nanofibers: a review

“…However, its high melting point combined with its low vapor pressure requires application of wet electrospinning, as common dry electrospinning is not capable of producing the desired NFs. By doing this, the electrospun fibers slowly solidify in a coagulation bath, in which the ionic liquid is replaced by a co-solvent, which is later removed by desiccation or freeze-drying (Quan et al 2010;Ciuzas et al 2021). Quan et al (2010) evaluated the electrospinning of cellulose dissolved in a hydrophilic ionic liquid, 1-butyl-3-methylimidazolium chloride (BmimCl), and also the influence of dimethyl sulfoxide (DMSO) as an additive in solutions with a higher concentration of cellulose.…”