Flame‐retardant treatment of Lyocell fibers and effects on various fiber properties. (7th June 2021)

• Record Type: Journal Article
• Authors: Peng, Kang; Meng, Yongwei; Zhang, Huihui; Yang, Gesheng; Shao, Huili
• Is Part Of: Fire and materials. Volume 46:Number 2(2022)
• Page Start: 487
• Page End: 495
• Publication Date: 2021-06-07
• Subjects: flame resistance -- hygroscopicity -- limited oxygen index -- Lyocell fiber -- mechanical property; Fire-testing -- Periodicals; Fire -- Periodicals; Materials -- Periodicals; 620.11217
• DOI: 10.1002/fam.2993
• Languages: English
• ISSNs: 0308-0501

Abstract

SUMMARY: Hexamethylolmelamine was used as a cross‐linking agent to graft 3‐(dimethylphosphono)‐ N ‐methylolpropionamide (MDPA) onto Lyocell fibers in a posttreatment process to reduce flammability. The effects of processing conditions on the mechanical properties and P content of the fibers were examined. The results show that increasing the MDPA concentration, microwave treatment time, baking temperature, and baking time increases the P concentration in the fibers, although the mechanical properties of the fibers are reduced to varying degrees. The optimal processing conditions comprise a 40% MDPA concentration, a 320 W microwave treatment for 3 minutes, and baking at 160°C for 5 minutes. Under these conditions, flame‐retardant Lyocell fibers with a breaking strength of 2.47 cN·dtex −1 and a limiting oxygen index of 34.6% were obtained, which meet the performance requirements for textile fibers. Thermogravimetric data indicate that the residual fiber mass after heating increased from 4.7% before treatment to 21.5% after treatment. There was only a minimal change in the hygroscopicity of the treated Lyocell fibers. In addition, after 30 washes, the limiting oxygen index was decreased to 26.5% while maintaining a good flame‐retardant effect.