Superhydrophobicity is a property frequently observed in plants and animals. This property is an effective mechanism for natural species to keep their surface clean. Inspired by this characteristic, SFT researchers have reported a new type of multifunctional cotton fabric with simultaneous superhydrophobic, antibacterial, UV protective, self-cleaning and photothermal properties. Dr Esfandiar Pakdel, Research Assistant Professor and a member of the Jockey Club (JC) STEM Lab of Sustainable Fibers and Textiles led by Prof. Wang Xungai, Global STEM Scholar and Chair Professor, developed a feasible finishing process based on the treatment of fabrics with formulations that contain polydimethylsiloxane (PDMS) and silver nanoparticles (AgNPs). Dr Pakdel and his colleagues showed that the treated cotton fabric is highly superhydrophobic where the applied fluorine-free coatings give rise to a water contact angle (WCA) of 171.3°, which is an excellent WCA value without using any type of fluorinated compound. The achieved superhydrophobicity is because of the increased surface roughness due to the embedded AgNPs and lowered surface energy resultant of the presence of PDMS. Furthermore, it was reported that although the AgNPs are embedded in the PDMS polymeric binder, efficient antibacterial activity against E. coli bacterium is obtained by increasing their concentration. The coated cotton fabrics have excellent UV protection levels that protect wearers against the harmful impacts of UV radiation. It was shown that the transmitted level of harmful UVA and UVB radiations through fabrics which could reach the skin of wearers is only 0.14% and 0.34%, respectively, thus indicating the high levels of protection. The developed cotton fabric also has a strong photothermal functionality which could come in handy for the development of advanced thermoregulating clothing and anti-icing coatings for cold environments. The fabric is washable with high fastness against numerous wash cycles, thus minimising the risk of leaching out AgNPs and deterioration of the obtained functionalities.
Full paper can be accessed at https://doi.org/10.1021/acsami.3c04598.
