THE INVESTIGATION OF THE LYOCELL FIBERMODIFIED BY AMMONIUM CHLORIDE——(II) THE INFLUENCE OF AMMONIUM CHLORIDE ON THESTRUCTURE AND PROPERTIES OF LYOCELL FIBERS

A mechanism why ammonium chloride can improve the mechanical properties of Lyocell fibers has been studied. The effects of ammonium chloride, which is used as a modifier, on the structure and properties of Lyocell fibers which are prepared by cellulose/NMMO·H_2O spinning system were investigated. The results show that the effect of draw ratio on the structure and mechanical properties of Lyocell fibers modified by NH_4Cl is different from those of common Lyocell. The crystal form of this Lyocell is a mixture of cellulose Ⅱ and Ⅲ. It is found it can remarkably improve the mechanical properties for adding amount of NH_4Cl into system. For the cotton cellulose/NMMO·H_2O solution (cellulose mass percentage 9%, (DP) 818), the tenacity of Lyocell can increase 30% when adding (0.5%) NH_4Cl into the system.