Tailoring flower-like Zn(OH)2 nanoarchitectures and stearic acid on cellulosic fibers for structurally robust superhydrophobic surface

Structurally robust nanostructures on the surface of matrix highly determine the durability of superhydrophobic surface of cellulosic materials. Traditionally, the hydrophobic inorganic-organic nanocomposites were physically coated on the surface of cellulose fibers, whereas the nanocomposite was easy to fall off under external force due to the weak interfacial interaction between inorganic materials and cellulose, restricting their practical application. In this work, a sort of structurally stable superhydrophobic cellulosic materials was elaborately designed by successive in situ synthesis of Zn(OH)2 nanoarchitectures and coating stearic acid (STA). The unique flower-like micro/nano structures as well as the presence of hydrophobic STA imparted the cellulosic materials with superhydrophobic behavior and the optimized water contact angle of synthesized STA@Zn(OH)2/paper nanocomposite was enhanced to 171°. Moreover, the resultant cellulosic nanocomposite also possesses excellent structural stability without STA and Zn(OH)2 fall off as well as hydrophobicity reduction after bending 100 times. Compared to bare filter paper, both tensile stress and elongation at break of optimized flower-like nanocomposite reached 14.04 MPa and 25.24% with 109.6% and 323.5% improvement, respectively. Furthermore, such superhydrophobic cellulose-based material also presented excellent anti-fouling and antibacterial performances. This work proposed a facial and efficient strategy to construct structurally stable superhydrophobic cellulose-based materials, displaying great potential application in food packaging and outdoor anti-fouling fields.