Abstract
Retaining the properties of pulp unaffected, the degree of crystallinity and the average size of crystallines are appreciably reduced, when a pulp is treated with ethylenediamine. In order to study the effect of reduced crystallinity on the reactivity of the sulphite pulp, such an amine treated pulp is subject to xanthation and acetylation and the reactivity of the material is compared with the untreated pulp. Following results are obtained :
1. After the alkali steeping, which is the first step of viscose making, the difference of crystallinity between the decrystallized pulp and the untreated pulp is scarcely found, so the properties of viscose from the former are not different from the latter.
2. In perchloric acid catalysed acetylation, when pretreated with glacial acetic acid, the decrystallization of pulp favors the reaction so much, that the solubility of the reaction product in the acetylation mixture is better than ordinary one. But without the pretreatment, the solubility of the acetate from the decrystallized pulp is not so good as one from the ordinary pulp.
3. In sulphuric acid catalyzed acetylation, the reactivity of the decrystallized pulp is reduced.
