Fiber Composition and Yarn-Spinning Methods Influence Microfiber Release, Study Shows
The way a garment is manufactured plays a critical role in determining the volume of microfibers it will release throughout a lifetime of wash and wear.
Fiber composition and yarn spinning systems have the “greatest influence” on microfiber release, according to a new study. The research—titled “Investigating the influence of yarn characteristics on microfibre release from knitted fabrics during laundering”—comes from the University of Leeds and was published in the peer-reviewed Frontiers of Environmental Science earlier this week.
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The study investigated the influence of various yarn characteristics on microfiber release from knitted fabrics and explored the generation of microfibers during the knitting process.
Alice Hazlehurst, Dr. Mark Sumner and Dr. Mark Taylor, all from the School of Design at the University of Leeds, found that the most significant quantity of microfibers was released from ring-spun (when fibers are twisted in a metal ring) lyocell. By contrast, the lowest amount was released from vortex-spun (when fibers are twisted using jets of air in a vortex) polyester.
“The yarn spinning system was also found to have a significant influence, with vortex-spun yarns consistently demonstrating lower microfiber release than corresponding ring-spun yarns, likely due to the reduced hairiness of yarns spun in the vortex systems,” the paper said. The importance of fiber damage incurred during the knitting process was also studied. “Several yarns demonstrated significantly greater microfiber release in knitted form compared to loose, hank form, but the scale of difference was found to be dependent on the fiber composition.”
The researchers found that unknitted polyester released more microfibers than unknitted cotton. However, “similar amounts” were released when the polyester was knitted—signaling that polyester “suffered less damage” than cotton during the knitting process. Microfiber release was “reduced” in tightly knitted fabrics during laundering. Still, manufacturers should consider fiber-fly: the “visible fluff” that comes off fabrics as they are knitted in factories, which was shown to increase microfiber release in washing.
Overall, vortex-spun yarns displayed a lower microfiber release than ring-spun yarns, as ring-spun yarns tend to be “hairier” than the vortex-spun yarns, which has been shown to increase microfiber release in washing.
“Our findings show that the entire process of textile production, down to the way yarn is spun, is important in the effort to limit microfiber release,” Hazlehurst said. “Manufacturers should contain these details in specifications of yarn spinning, as well as the fiber type, to help clothing designers make more informed choices.”
The researchers agreed that changes to a yarn’s fiber composition, along with the yarn-spinning system used, would have the “greatest influence” in terms of reducing microfiber shedding. However, these details aren’t currently included in product specifications, making it more difficult for brands to decide what garments will or won’t release more microfibers.
“We know cotton produces more microfiber than polyester and people assume that cellulose—from cotton—is less worrying than microplastic because it’s natural,” Dr. Taylor said. “But the truth is that we don’t have enough information about the impacts of these fibers on humans, aside from knowing they can take hundreds of years to biodegrade and can have a negative impact on marine life.”
Meanwhile, the University of California in San Diego and materials science company Algenesis have been working on combatting the impacts of microplastic pollution. And new research shows that the duo’s plant-based polymers biodegrade—including at the microplastic level—in under seven months, per a paper published in Nature Scientific Reports.
“We’re just starting to understand the implications of microplastics. We’ve only scratched the surface of knowing the environmental and health impacts,” said Michael Burkart, one of the paper’s authors and an Algenesis co-founder. “We’re trying to find replacements for materials that already exist, and make sure these replacements will biodegrade at the end of their useful life instead of collecting in the environment. That’s not easy.”
