Structure and properties of flame-retardant Lyocell fibers prepared by blending method

Two flame retardants, melamine polyphosphate (MPP) and modified melamine cyanurate (MCA), were examined and added to a cellulose solution to fabricate flame-retardant Lyocell fibers Lyocell-MPP and Lyocell-MCA, respectively, via dry-wet spinning. Compared with the non-modified Lyocell fiber (without flame retardant), the flame-retardant fibers produced a higher amount of carbon residue during combustion, whereas the heat release capacity, peak heat release rate, and total heat release decreased, indicating that the flame-retardant fibers present a lower fire risk. The limit oxygen index values of Lyocell-MPP and Lyocell-MCA were 26.5% and 27.1%, respectively, complying with the flame-retardant standard. The crystallinity and mechanical properties of the flame-retardant fibers decreased relative to those of the non-modified Lyocell fiber. Furthermore, the wearability of the flame-retardant fibers was studied-both flame-retardant fibers displayed good washing resistance properties and improved hygroscopicity but a lower dyeing performance than the non-modified Lyocell fiber.

Automated summary

The study found that adding flame retardants MPP and MCA could produce flame-retardant fibers Lyocell-MPP and Lyocell-MCA, which have a lower fire risk and good wash resistance and moisture absorption, but poor dyeing performance.