Improving Mechanical Textile Recycling by Lubricant Pre-Treatment to Mitigate Length Loss of Fibers

Abstract

Although there has been some research on how to use short fibers from mechanically recycled textiles, little is known about how to preserve the length of recycled fibers, and thus maintain their properties. The aim of this study is to investigate whether a pre-treatment with lubricant could mitigate fiber length reduction from tearing. This could facilitate the spinning of a 100% recycled yarn. Additionally, this study set out to develop a new test method to assess the effect of lubricant loading. Inter-fiber cohesion was measured in a tensile tester on carded fiber webs. We used polyethylene glycol (PEG) 4000 aqueous solution as a lubricant to treat fibers and woven fabrics of cotton, polyester (PES), and cotton/polyester. Measurements of fiber length and percentage of unopened material showed the harshness and efficiency of the tearing process. Treatment with PEG 4000 decreased inter-fiber cohesion, reduced fiber length loss, and facilitated a more efficient tearing process, especially for PES. The study showed that treating fabric with PEG enabled rotor spinning of 100% recycled fibers. The inter-fiber cohesion test method suggested appropriate lubricant loadings, which were shown to mitigate tearing harshness and facilitate fabric disintegration in recycling.

Textile and Product Development from End-of-Use Cotton Apparel: A Study to Reclaim Value from Waste

“…Mechanical recycling is one of the main methods to recycle pre-consumer cotton textile waste [6]. The shredding and tearing process in the mechanical recycling shortens the fiber length and reduces fiber quality, so it is a downcycling process to produce low-value products such as rags or insulation materials [32], or the mechanically recycled textiles need to be blended with a high percentage of new fibers in high-quality fabric production [6]. This research explored different mechanical recycling methods to recycle post-consumer cotton waste and developed high-value products including bags, a hat, garments, cell phone and glasses cases, and decorative textiles from the recycled materials.…”

“…Apparel brands such as Patagonia, Swany America, and Quiksilver in France are members of Teijin's "eco circle" program and develop products using Teijin's chemically recycled Eco Circle TM polyester fibers [31]. The shredding and tearing processes in the mechanical recycling shorten the fiber length and reduce fiber quality, which may result in low value products such as rags or insulation materials [32], or the blending of mechanically recycled materials with a high percentage of new materials in fabric production to assure fabric quality [6].…”

Towards sustainable textile sector: Fractionation and separation of cotton/ polyester fibers from blended textile waste

“…This treatment showed to be successful in reducing the loss of fiber length, decreasing inter-fiber cohesion, and facilitating the tearing process. The authors showed that it was possible to rotor-spin 100% of mechanically fractionated fibers after this treatment [43].…”

Life Cycle Assessment (LCA) of MWool® Recycled Wool Fibers

“…An additional problem is that recycled wool fibers are generally of lower quality than virgin wool fibers, mainly due to the shortening of fiber lengths [18]. It can be necessary to mix short fibers with virgin fibers to enable respinning into yarns and achieve the required quality [24][25][26]. The Circular Footprint Formula's (CFF, [27]) attempts to capture this aspect in environmental analyses of textiles could be applied as has been discussed in detail in Wiedemann et al [16].…”