Beyond a second life: Mechanical recyclability of woven fabrics containing recycled wool

Woven fabrics containing high proportions of post-consumer and/or post-industrial wool are manufactured for certain types of clothing, e.g. suiting, but their suitability for further mechanical recycling in a closed loop is not widely understood. Therefore, representative, industrially manufactured woven fabrics containing mechanically recycled post-consumer wool waste (2 % - 55 %), and post-industrial/process wool waste (6 % - 84 %) produced by the MWool® process were systematically studied, to determine levels of fibre breakage during textile processing and prospects for further recycling. The initial mean fibre length in woven wool fabrics was negatively correlated to the percentage retained mean fibre length after mechanical recycling, to a greater extent than in wool knitwear. In addition to fibre breakage in mechanical recycling, finishing of woven fabrics containing recycled wool to enhance fabric aesthetics and performance, using fulling, brushing, raising and calendering processes also lead to fibre breakage. Due to the relatively short fibre lengths in the woven fabrics, subsequent recycling leads to breakage, but to a lesser extent (average retained fibre length of 84 %) than for recycled knitted fabrics (average retained fibre length of 72 %), even though the absolute mean fibre length of the woven fabrics is shorter than for knitted fabrics. However, woven fabrics containing MWool® recycled wool still have potential to be recycled at least once more as part of a closed loop system, before fibre breakage would necessitate diversion to other end-uses or waste streams. Innovative finishing methods that limit frictional forces on the fabric surface (instead of brushing or raising) are needed to preserve fibre length and improve the recyclability of woven fabrics containing recycled wool.