Preparation and properties of chemical cellulose from ascidian tunic and their regenerated cellulose fibers

Chemical cellulose (dissolving pulp) was prepared from ascidian tunic by modified paper-pulp process (prehydrolysis with acidic aqueous solution of H,SO,, digestion with alkali aqueous solution of NaOH/Na2S, bleaching with aqueous NaOCl solution, and washing with acetone/water). The a-cellulose content and the degree of polymerization (DPw) of the chemical cellulose was about 98 wt % and 918, respectively. The Japanese Industrial Standard (JIS) whiteness of the chemical cellulose was about 98%. From the X-ray diffraction patterns and C-13-NMR spectrum, it was found that the chemical cellulose obtained here has cellulose 10 crystal structure, A new regenerated cellulose fiber was prepared from the chemical cellulose by dry-wet spinning using N-methylmorpholine-N-oxide (NMMO)/water (87/13 wt %) as solvent. The new regenerated cellulose fiber prepared in this study has a higher ratio of wet-to-dry strength (<0.97) than commercially regenerated cellulose fibers. (C) 2002 Wiley Periodicals, Inc.