CHARACTERIZATION OF TOBACCO STALK BLEACHED PULP

摘要

Tobacco stalks were treated by two pulping processes: acetone organosolv, using different catalysts (e.g. H2SO4, HCl, FeCl3/HCl), and soda-anthraquinone (soda-AQ). Resulting pulps were bleached with sodium chlorite in acetic acid solution. Cross polarization/magic angle spinning solid state NMR (CPMAS-NMR) of bleached pulps (BPs) indicated the presence of characteristic peaks associated with the anhydroglucose repeating unit of cellulose. Both CPMAS-NMR and X-ray diffraction results showed that the crystallinity indices of celluloses from acetone organosolv BPs were higher than that of the cellulose from soda-AQ BP. Furthermore, bleached pulps were treated with phenyl isocyanate in order to yield cellulose tricarbanilates (CTC). Weight average (DPw) and number average (DPn) degree of polymerization of CTCs were determined by size exclusion chromatography. Both DPw and DPn values of CTC obtained from soda-AQ BP were higher than that of CTCs obtained from acetone organosolv BPs.