FIBERS FROM DMAC-LICL SOLUTIONS OF STEAM EXPLODED WOOD

Poplar wood was steam exploded under various experimental conditions (230-degrees-C, 120-360 sec) and was then dissolved in dimethylacetamide-lithium chloride (DMAc-LiCl). Solutions of different concentrations (c(p) 4-10%) were obtained without any activation. Mesophases were not formed in any of the conditions tested. The good spinnability of the solutions led to wood fibers that were evaluated in terms of physico-mechanical properties and morphological and supramolecular characteristics. The tensile strength and the modulus of the wood fibers, improved through delignification treatments, were comparable to those of conventional rayons. After annealing treatments at 260-degrees-C in protic solvent, X-ray and CP MAS C-13-NMR experiments revealed evidence of a marked modification of the fiber supramolecular structure. (C) 1994 John Wiley & Sons, Inc.