Superhydrophobic Coatings on Textiles and Papers

Abstract

Superhydrophobic textiles and papers have attracted considerable attention due to their unique wettability and great potential for applications in fundamental research and industrial areas. In this chapter, first methods for the fabrication of superhydrophobic textiles and papers by increasing the surface roughness and decreasing the surface energy are overviewed, then the evaluation of their superhydrophobicity is summarized. The most frequently used parameters are contact angle, sliding angle, water shedding angle, water repellency grade and hydrostatic pressure resistance. Low mechanical durability is a key issue restricting their application. The mechanical durability is usually evaluated by abrasion, washing, impact, stretching and torsion tests, etc. To improve the mechanical durability, covalent bonding, cross-linking in coatings, employment of elastic composites, self-healing and multi-layer design are the approaches usually adopted. Finally, functionalization of superhydrophobic textiles and papers is introduced, including self-cleaning, hemostatic textiles and oil–water separation, anti-scalding, anti-bacterial and flame-retardant properties. For the further development and applications of superhydrophobic textiles and papers, high mechanical durability, environmentally friendly fabrication methods and low preparation costs are the main challenges. Waterborne, durable, non-toxic and low-cost superhydrophobic textiles and papers are desired, and purposeful design and functionalization of superhydrophobic textiles and papers are also necessary for their real-world applications.