R&D Trends of Eco-Friendly Yarns – Bio-Based Yarns

Bio-based yarns take renewable biomass as raw materials for fiber spinning. Based on feedstock origins, we split them into three categories: virgin bio-based yarns, regenerated bio-based yarns and synthetic bio-based yarns.

First, virgin bio-based yarns adopt natural fibers from plants and animals and go through physical spinning processes. Common examples include cotton yarn, linen yarn and wool yarn. Second, manufacturers produce regenerated bio-based yarns from natural fibers via chemical dissolution and regeneration techniques. Typical varieties cover viscose yarn, milk protein fiber yarn and chitosan fiber yarn. Third, synthetic bio-based yarns form after the polymerization of biomass monomers, with bio-based polyamide and bio-based PET polyester fiber as mainstream feedstocks.

These yarns feature abundant raw material supplies, renewability and flexible functional modification. Therefore, developing bio-based yarns greatly helps the textile industry fulfill its green and carbon reduction goals.

Bio-based polyamide 56 (PA56) is lightweight, soft and wear-resistant, so manufacturers widely use it to develop eco-friendly bio-based yarns. Zhuohui produces core-spun composite yarns with full-polyester Sirofil spinning technology. His research shows that bio-based PA56 filament works as core yarn to deliver better moisture management, breaking elongation and elastic recovery than regular PET filament. Yet this core material brings weaker fiber cohesion at the same time. Blending extra bio-based PA56 into sheath fibers improves composite yarn’s breaking strength and elastic recovery. However, excessive PA56 content ruins yarn evenness and raises hairiness. For this reason, producers need to find an optimal blending ratio to balance comprehensive performance. In another study led by Xia Changlin, bio-based PA56/PET blended yarn gains optimal mechanical properties when PA56 accounts for 20% of total weight. Besides, Fonte achieves high-efficiency indigo dyeing on bio-based PA56/cotton blended yarn, and finished fabrics reach above Grade 3 in color fastness.

In one relevant trial, Liu Ting adopts semi-worsted spinning to produce bio-based banana stem fiber paired with ECOCIRC® Antibio® antibacterial fiber at an 85:15 blend ratio. Compared with pure banana stem fiber yarn, this blended product boosts breaking strength by 31%, lowers unevenness and hairiness index, and upgrades overall yarn quality.

Meanwhile, Ma Xiaofei proposes a production route for high-efficiency antibacterial bio-based yarn with an integrated dyeing and bacteriostasis process. He mixes antibacterial agents evenly with dyestuffs before feeding the mixture into all-in-one dyeing and drying machinery. This integrated procedure unifies two processing steps and lifts the overall production efficiency of bio-based yarns.

In short, these research findings offer practical references for further application of bio-based yarns in apparel production.