ON THE EXISTENCE OF NA-CELLULOSE I<sub>I</sub> AND I<sub>II</sub> AND THIER RELATION WITH CRYSTALLINE STRUCTURE OF ORIGINAL CELLULOSE

It was found that there was a difference between X-ray diffractograms of Na-Cellulose I derived from the cellulose I family (I and IIII) and that from the cellulose II family (II, IIIII and IVII), and we calssified them as Na-Cellulose II and Na-Cellulose III, respectively. Both Na-Cellulose II and III regenerated cellulose II by washing with cold water. When decomposed with hot water, however, Na-Cellulose II regenerated mixture of cellulose I and II, and Na-Cellulose III regenerated cellulose II. Namely, Na-Cellulose has memory of the crystalline structure of the original cellulose.As described in our previous paper, the chain conformation of cellulose is thought to be a difference between cellulose I and II families, the former has “bent” type and the latter has “bent and twisted” type comformation.The memory of the original structure may be due to the retaining of chain conformation during meroerization and regeneration. When Na-Cellulose II is decomposed by cold water, the chain conformation is changed from “bent” to more stable “bent and twisted” type owing to strong swelling and hydration, and cellulose II was regenerated.