Surface engineered long-lasting antibacterial Janus cotton fabrics with excellent moisture/thermal management properties

The hydrophilic property of traditional cotton fabrics invariably facilitates sweat absorption, potentially leading to discomfort such as cold and clammy sensation, and even promoting bacterial proliferation. Herein, we developed a Janus cotton fabric using a surface engineering strategy combining "graft through" and "mist polymerization" methodologies. Through the "graft through" polymerization of methacryloyloxyethyl dodecyl dimethyl ammonium bromide (DMDB), we constructed a well-designed antibacterial coating on the fabric with amphiphilic properties. The resulting polymer, PDMDB, imparts highly efficient and durable antibacterial properties to the cotton fabric, achieving a bcteriostatic rates against S. aureus and E. coli of > 99.9 %. Even after undergoing 150 washing cycles, the residual bactericidal efficacy remains above 99 %. Additionally, the reversible hydrophilic-hydrophobic nature of PDMDB successfully enables the construction of a Janus structure on cotton fabrics via "mist polymerization". Benefiting from its comprehensive design, the Janus cotton fabrics realize a superior directional liquid transport property. Its water evaporation rate is 1.3-1.5 times higher than that of the original cotton fabric in continuous outdoor moisture management, while maintaining body temperature 5.63 C lower than that of the surrounding environment. It is worth mentioning that our approach utilizes abundant raw materials and facile modification technologies, thereby providing a favorable guarantee for the mass production and use of Janus cotton fabrics.