A Rapid Identification Method for Lyocell Fibers with Different Cross-Linking Degrees Via ZnCl2 Solution

Lycell fiber, which combines the advantages of synthetic fibers and natural cellulose fibers, is one of the most promising textile raw materials with the best market feedback in this century. However, there is currently no accurate method for identifying different cross-linking degrees of lycell fiber. This study investigated the swelling and dissolution behaviors of lyocell fibers with different crosslinking types (uncrosslinked G100, semi-crosslinked LF, and fully crosslinked A100) in acidic and alkaline solutions. The method for accurately identifying different crosslinking types of lyocell fibers based on ZnCl2 solution was developed, along with analysis of factors influencing crosslinking properties. Results revealed significant differences in dissolution times of the three lyocell fibers at 90°C in a 70% ZnCl2 aqueous solution, with dissolution durations of 30 min, 180 min, and 450 min, respectively. Therefore, the 70% ZnCl2 solution solution can be effectively used to distinguish these three lyocell fiber types. The establishment of this method holds significant implications for production quality control of lyocell fiber fabrics and standardization of domestic and international market trade practices.