Janus cotton fabric with Dual-Discrepancies in surface energy and porosity for efficient thermal and moisture management

Abstract

The Janus fabrics offer potential advantages in moisture management for a comfortable microclimate between our bodies and the environment, but challenges remain in achieving desirable unidirectional sweat transfer and integrating wearing comfort, cost-effectiveness, and fabrication scalability. Here, cotton fabrics are modified on their opposing surfaces to create a Janus structure with dual discrepancies in surface energy and fabric porosity, resulting in improved water transport capability and a well-balanced combination of the mentioned properties. The hydrophobic surface was created by covalently grafting a block copolymer, poly(acrylic acid)-b-poly(lauryl methacrylate), onto one side of a cotton fabric using a “mist polymerization” technique. Porosity differentiation was then achieved by electrospinning silk fibroin (SF) onto the opposite side. The resulting dual-discrepancy in the fabric synergistically enhances its unidirectional transport capability, achieving an outstanding water evaporation rate of 3.0 kg m−2 in 6 h, and at least 2 °C evaporative cooling compared with other conventional fabrics such as cotton and PET. This study demonstrates valuable insights into the development of smart textiles that provide a comfortable microclimate for the human body.