Spinnability of Low-Substituted Hydroxyethylcellulose Sodium Hydroxide Aqueous Solutions

Ethylene oxide was used to etherify alkali cellulose with a low substitution degree to replace carbon disulfide to generate cellulose xanthogenate by viscose technology. The resultant low-substituted hydroxyethylcellulose (LSHEC), with molar substitution of 0.49, was used to attempt to spin LSHEC fibers under spinning and coagulation conditions identical to those used for industrial rayon fibers. The spinnability of LSHEC was investigated by the variation of the storage modulus, loss modulus, and complex viscosity with the concentration of the LSHEC spinning solutions and temperature. It was found that the dissolution of LSHEC in sodium hydroxide aqueous solutions was an exothermic process, whereas the gelation of LSHEC was an endothermic process. Spinning conditions, comprising the concentration of the spinning solutions and corresponding spinning temperatures, were derived from the gelation onset curve theoretically. Moreover, combinations of the concentration of the spinning solution and the temperature of the coagulation bath could be predicted by the gelation onset curve. Finally, LSHEC fibers were prepared under the spinning conditions based on the gelation onset curve. The as-spun LSHEC fibers had dry and wet tensile strengths of 1.59 and 0.47 cN/dtex, respectively, with a 0.30 ratio of the wet tensile strength to the dry tensile strength. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 117: 767-774, 2010