Rational design of perfluorocarbon-free oleophobic textiles

Abstract

Water- and oil-repellent fabrics have global application within the textile industry and as technical apparel. Fabric finishes utilizing perfluoro compounds (PFCs) are known to uniquely render textiles both water and oil repellent. However, PFC-based finishes are not sustainable because they compromise environmental and human health, and garment factories have accordingly begun to phase out PFC usage. This is problematic, as all previous studies on fabric finishes indicate that oil repellency cannot be achieved without perfluorination. Here we develop design parameters for fabricating oil-repellent textile finishes using PFC-free surface chemistries. By adding a secondary, smaller length-scale texture to each fibre of a given weave, robust oil repellency is achievable when the texture size, spacing and surface chemistry are properly controlled. For example, a PFC-free, oil-repellent jacket fabric is fabricated that exhibits oleophobicity towards canola, olive and castor oil in addition to synthetic sweat. The textile remains non-wetted for liquids with surface tension as low as 23.9 mN m−1. The equations developed in this work allow for the rational design of oil-repellent textile finishes that do not utilize perfluorinated substances. Perfluorochemicals render fabrics water and oil repellent; however, their use poses environmental and health risks. Here, the authors show the rational design of textile finishes with excellent oil repellency without adopting any perfluorinated substances.