Study of a newly structuralized meta-aramid/cotton blended yarn for fabrics with enhanced flame-resistance

This paper presents a study on a newly structuralized meta-aramid/cotton blended yarn for fabrics with enhanced flame-resistance. In this study, a new type of "marl yarn" resembling structure for cotton/aramid yarns was proposed with an aim to lower the flammability of cotton fiber strands within the yarn and thus enhance the flame resistance of the blended yarns and the resultant fabrics. To facilitate the formation of marl yarn structure, a modified device was developed that can be attached to the ring spinning machine for yarn production. Yarn structure was examined and the effects of the blending ratio of aramid/cotton fibers and yarn structure on the yarn flammability and physical properties were investigated. The results showed that a marl-like yarn structure was formed wherein a small amount of meta-aramid fibers were concentrated to form fiber strands, which served as effective fire barriers, hindering the afterflame/afterglow of cotton fibers. The experimental results demonstrated that the marl structured yarn exhibited lower yarn flammability in terms of afterflame, afterglow, damage length and limiting oxygen index (LOI) as well as possessing similar physical properties compared with conventional evenly blended yarn. By using the marl structured yarns developed, meta-aramid/cotton blended woven fabrics were produced and their flammability and physical properties were evaluated. The results showed that the fabrics using the marl structured yarns had a higher minimal flame application time for ignition and LOI as well as a lower flame spread speed than fabrics using evenly blended yarns.