Superefficient and robust polymer coating for bionic manufacturing of superwetting surfaces with “rose petal effect” and “lotus leaf effect”

Mimicking the superwetting behaviors of nature creatures is advantageous for the development of multifunctional surfaces. Superhydrophobic surfaces are desired for applications such as self-cleaning, drag reduction, anti-staining, anti-corrosion, oil-water separation, etc. Herein, a superefficient approach is proposed to produce a robust ultrahigh molecular weight polyethylene (UHMWPE) coating on various substrates by dripping and drying UHMWPE solutions. The superhydrophobic surfaces can be tuned between Cassie impregnating state and Cassie state, which resembles the “rose petal effect” and “lotus leaf effect”, respectively, by simply adjusting the quenching temperature and the solvent system. UHMWPE/ortho-xylene biphasic solution resulted in a wrinkled morphology with a high-adhesion superhydrophobic surface, while the UHMWPE/ortho-xylene/cyclohexanone triple-phase solution led to a highly porous morphology with a low-adhesion superhydrophobic surface. The micro-nano structured surfaces displayed promising applicability in droplet transportation, selective oil absorption, anti-staining, and self-cleaning. They also possess superior stability and durability against various liquids and mechanical impact. This work provides a highly efficient approach to produce versatile bionic superhydrophobic coatings with tunable superwetting states.