Textile Insight

Arc'teryx Partners with UBC on Next-Gen Water- Oil-repellent Fabric. By Kathlyn Swantko hile many companies and researchers in the outdoor market are work- ing to eliminate perfluoro-carbons (PFCs) in fabric treatments, we have yet to see a large-scale commercialization of a water- and oil-repellent finishes that don't contain PFCs," explains Mary Glasper, materials developer at Arc'teryx, "and the world of DWR has been an especially tricky area to address. Our partnership on this issue is a meaningful way to contribute, while making a meaningful change for Arc'teryx to reach our goal of reducing our greenhouse gas emis- sions by 65 percent in intensity by 2030." The University of British Columbia (UBC)- Arc'teryx three-year project, started in early 2019, looks to fabricate oil-repellent fabrics without the use of PFCs, as the toxicity of PFCs can remain in the environment for hundreds of years. "This means the concentration of PFCs continually increase in the environment and then, through drinking water, also remain within the human body and blood," explains Kevin Golovin, leading UBC professor on the research. "For every liter of blood, the average human body contains four nano- grams of perfluorooctanoic acid, one of the toxic by-products of PFC production and degradation." After receiving funding approval from the Natural Sciences and Engineering Research Council of Canada (NSERC), Golovin hired Ms. Sadaf Shabanian, PhD student at UBC Okanagan's School of Engineering, as the lead author on the study. The Research As the research began, it became clear that the fabric construction, the specific weave, twist, denier, etc., was as important as the coating when it came to repellency calculations. Another significant finding was that PFCs were not unique in their ability to repel oil. Other materials like waxes and silicones could also repel oil, although not as well as the PFCs. "Our initial breakthrough came when Sadaf's research showed that by using the theory of wettability, we could better under- stand how a fabric should be coated in order to repel oily substances," explained Golovin. "Since materials like silicones have inferior repellency compared to PFCs, they would need the help of an additional length-scale of texture. So, we calculated how oil-repellency would change if each fiber was decorated with small, spherical particles. It turned out that this second level of texture allowed the fibers to mimic perfluoro-carbon chemistry!" On this basis, it was theorized that if the size/spacing between particles were within certain ranges, oil-repellency was possible without the use of PFC compounds. However, a demonstration of the theory showed that by simply choosing a fabric/ chemistry combination that met UBC's derived criteria, the team discovered that a fabric could become oil-repellent by using plain silicone chemistry. Arc'teryx provided a plain weave, highly twisted inner-liner fabric for UBC to continue the research. In a few weeks, Sadaf was able to demonstrate that oil-repellency can be achieved without using PFCs, with envi- ronmentally benign materials like silicones, something that was previously thought impossible. Liquids like vegetable oil, syn- thetic sweat, water-ethanol mixtures were all repelled by Sadaf's fabric finish. Glasper added, "The IP created in this project will remain exclusive to Arc'teryx for some time, but our vision is to commercialize a product the entire apparel industry can benefit from, not just ourselves." l W EDUCATION | UNIVERSITY OF BRITISH COLUMBIA (UBC) Eco-First Performance Caption: Prof. Kevin Golovin and doctoral student Sadaf Shabanian investigating the liquid repellency of an oleophobic fabric (a chemically modified textile that can repel droplets of oil). Kathlyn Swantko, president of the FabricLink Network, created www.TheTechnicalCenter.com for Industry networking and marketing of specialty textiles, and www.fabricklink.com for consumer education involving everything fabric. Contact: kgswantko@fabriclink.com textileinsight.com September/October 2020 ~ Textile Insight • 33 For more information: Kevin Golovin, Asst. Professor, Mechanical, School of Engineering, at kevin.golovin@ubc.ca, 250.807.9774 Sadaf Shabanian, PhD student / lead author on the study, sadaf.shabanian@ubc.ca Mary Glasper, materials developer at Arc'teryx, mary.glasper@arcteryx.com

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