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

Abstract

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 nonmodified 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.

N‐methylmorpholine‐N‐oxide molecules coated ammonium polyphosphates for dope spinning of flame‐retardant lyocell fiber

“…23 However, while there has been considerable research on enhancing the flame retardancy of plastics through blending with APP, little attention has been given to fabricating regenerated cellulose materials using this approach. 24 Mechanistically, the dissolution of cellulose in NMMO is attributed to the strong dipolar nature of the active N-O group. This group's oxygen forms one or two hydrogen bonds with the hydroxyl groups on the cellulose glucose unit, leading to the intramolecular destruction of intermolecular hydrogen bonds.…”

“…Similarly, blending unsaturated polyester resin with 30% APP improved its UL‐94 rating from no rating to V‐0, accompanied by an increase in the LOI value from 19.9% to 36.3% 23 . However, while there has been considerable research on enhancing the flame retardancy of plastics through blending with APP, little attention has been given to fabricating regenerated cellulose materials using this approach 24 …”