抄録
Some preliminary experiments on the preparation of cellulose phosphate by the urea-phosphoric acid method and comparison of the electrolytic dissociation of cellulose phosphate with those of analogous polyelectrolytes led to the following conclusions:
1) Autooxidation of cellulose in the condition of phosphorylation which leads to depolymerization can be avoided by conducting the phosphorylation in atmospheres of inert gases. The adsorption equibrium of urea and phosphoric acid to cellulose is established comparatively rapidly, but the difference between the ratio of urea to phosphoric acid adsorped to pulp fiber and the ratio in the aqueous mixture showes that urea is adsorbed by pulp fiber more strongly than by phosphoric acid.
Pretreatment with various cellulose-swelling agents including some kinds of inorganic salts is useful to increase the amount of phosphorus combined with cellulose and phosphorus content is related to the degree of swelling. 2) The characteristics of water soluble cellulose phosphate in electrolytic dissociation and in the change of viscosity show a considerable resemblance to those of other polyelectrolytes which bear dibasic acid groups or two kinds of dissociating groups, but the neighboring groups in cellulose phosphate have the least effect on electrolytic dissociation. This indicates that the ionization strength of phosphoric acid group is least affected by the neighboring groups.
