Influence of process parameters on the structure formation of man‐made cellulosic fibers from ionic liquid solution

Abstract

The influence of dry-jet wet spinning parameters on the production of man-made cellulosic fibers from 13 wt % cellulose/1,5-diazabicyclo[4.3.0]non-5-ene acetate solutions was investigated. The spinneret nozzle diameter, extrusion velocity, draw ratio, and coagulation bath temperature were the studied parameters. The production of highly oriented fibers was favored by selecting higher extrusion velocity and lower spinneret diameter. A spinneret size of 100 mm and a draw ratio of 6 were sufficient to highly orient the cellulose macromolecules and achieve tenacities above 40 cN/tex (600 MPa). Total orientation assessed via birefringence measurement, tenacity, and Young's modulus values reached a plateau at a draw of 6 and no further development in properties was observed. A temperature of the aqueous coagulation bath of 15 8C slightly promoted greater orientation of the fibers by hampering structural changes of the cellulose macromolecules in the nascent solid fibers. Furthermore, the determination of the elongational viscosity of the liquid thread via the measurement of radial force tensor was tested and showed promising results. V C 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43718.

Processing of Cellulose Using Ionic Liquids

“…Apart from several ILs of the imidazolium family, a spinning process based on the so called Ionocell process, which uses [DBNH][OAc], was developed by Sixta et al . This process is close to industrial conversion, since garments like ties or shirts are already produced, finished, and dyed .…”

“…This process is close to industrial conversion, since garments like ties or shirts are already produced, finished, and dyed . Several important parameters like the influence of pulp source, degree of polymerization, the mass distribution, as well as process parameters like the draw ratio, the air gap size, and the temperature of the coagulation bath were studied . Furthermore, Ma et al.…”

“…[44] An appropriate IL-system, [EMIM][OAc] was proposed for wet spinning of cellulose, including details on the rheology of the spinning dopes, characterization of the fiber, and the recycling of ILs. [29] Apart from several ILs of the imidazolium family, a spinning process based on the so called Ionocell process, which uses [DBNH][OAc], was developed by Sixta et al [21,22,[45][46][47] This process is close to industrial conversion, since garments like ties or shirts are already produced, finished, and dyed. [21] Several important parameters like the influence of pulp source, degree of polymerization, the mass distribution, as well as process parameters like the draw ratio, the air gap size, and the temperature of the coagulation bath were studied.…”

“…[21] Several important parameters like the influence of pulp source, degree of polymerization, the mass distribution, as well as process parameters like the draw ratio, the air gap size, and the temperature of the coagulation bath were studied. [22,46] Furthermore, Ma et al reported on the recycling of cellulose waste materials for new fiber production. [48] A summary of the mechanical properties of cellulosic fibers spun from different ILs is provided in Table 1.…”

Identifying breach mechanism during air‐gap spinning of lignin–cellulose ionic‐liquid solutions

“…Previous experimental work on air‐gap spinning has linked the rheology of solution to spinnability or the critical draw ratio in a nonsystematic fashion . Related studies also focus on the effect of process parameters or type of coagulant on fiber properties . Haward et al ., investigated the elongational behavior of a cellulose‐EMIMAc solution with capillary break‐up elongational rheology (CaBER) measurements.…”