Exploring the underwater air-retaining ability and thermal insulating effect of terry fabrics inspired by Salvinia molesta

The plant leaf of Salvinia molesta can retain an air layer underwater due to the hydrophobic and elastic eggbeater-shaped hairs on its surface, which have potential applications in thermal insulation devices. In this research, terry fabrics are explored to mimic the air-retaining ability of the salvinia leaf for potential application in overwater life-saving appliances. The surface structure of the fabric is analyzed and the superhydrophobicity is obtained by hydrophobic treatment combined with microscale roughness brought by the fabric texture. The air volume change and the thermal insulation tests demonstrated that terry fabrics, F1 and F3, can retain an air layer on their surfaces and hold air in between the fibers and inside the loops for a long time underwater, which would provide thermal insulation and buoyancy force—the two key features of life-saving appliances.