Authors: Yoshiharu Nishiyama Shigenori Kuga Takeshi Okano
Publish Date: 2000/12
Volume: 46, Issue: 6, Pages: 452-
Abstract
We studied the crystalline conversion of cellulose fiber from cellulose I to cellulose II mercerization by Xray diffraction focusing on the putative chainpolarity conversion from parallel to antiparallel The structural change of Nacellulose was examined during stepwise changes in NaOH concentration Either Nacellulose I or Nacellulose II was formed depending on the initial NaOH concentration Once formed both structures were stable and did not interconvert to each other when the NaOH concentration was changed Such stability indicates that the paralleltoantiparallel conversion is not likely to take place in the crystalline region of Nacellulose Regeneration of cellulose II from both forms of alkali cellulose proceeded with the formation of 044 nm lattice plane corresponding to the sheet of 1 ¯1 0 plane of cellulose II showing that the molecular stacking due to van der Waals interaction is the driving force of the formation of cellulose II A mechanism was proposed whereby the geometry of the cellulose molecule allows close fitting of the hydrophobic faces only in the antiparallel arrangement thus driving formation of the antiparallel structure of cellulose II
Keywords: