Crystalline transformation of native cellulose from cellulose I to cellulose II polymorph by a ball-milling method with a specific amount of water

We have demonstrated for the first time that a mechano-chemical treatment of native cellulose with a specific amount of water (similar to30 wt%) present in the cellulose solid state caused the crystalline transformation from cellulose I into cellulose II polymorph. X-ray diffractometry was used to show that the extent of transformation into cellulose II increased with milling time. This specific phenomenon can be explained by considering the chain mobility in the cellulose-water system, because T-1(1H) measurement shows that cellulose molecules are most mobile when the water content is around 30 wt%, and thus are favorable for molecular rearrangement under external forces.