Effect of concentrated sulfuric acid and nitroethane on insoluble residues in acetylating medium of cellulose acetate prepared from low grade pulps

Cellulose acetate was prepared from locally available low grade pulps containing α-cellulose in the range of 79–94%. The chemical and spectroscopic characterization confirmed the acetylation of all the cellulosic sources studied in the work. The effect of concentrated sulfuric acid as a catalyst and nitroethane as a solvent in the acetylation medium in reducing the insoluble residues was studied. The gravimetric analysis has indicated that these reagents reduce the insoluble residues. This was further confirmed by the optical microscopic photographs. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1765–1771, 2005