The Liquid Ammonia Treatment of Cotton Fibers-The Structural Changes of Cotton Fibers under Various Treatment Conditions in Practical Units

Abstract

The structural changes of cotton fibers by practical liquid ammonia treatment under four different conditions were investigated. Two liquid ammonia units were used, one of which had one drying cylinder and the other had two cylinders. The running speed of each unit was set at high or low. In each unit, the lattice type I did not decrease even after long ammonia wetting, and as the drying time increased, the lattice typeIII increased, the amorphous region also decreased. Therefore, regarding practical liquid ammonia treatment, the changes in the crystal structure are thought to occur as follows: Almost all cellulose changes to ammonia cellulose after short ammonia wetting, and along with the removal of the ammonia, the lattice type III increases, the amorphous region decreases and the residual ammonia cellulose converts to the lattice type I. It was found that after liquid ammonia treatment the pore volume corresponding to the PEG radius over 1.1nm and the water retention decrease, the dry and wet crease recovery angle, the tear strength, the tensile strength and the dye uptake increase. The degree of decrease or increase depends on the degree of drying respectively.