One-pot, template-free synthesis of a robust superhydrophobic polymer monolith with an adjustable hierarchical porous structure

Abstract

We fabricated a porous polymer monolith with tunable hierarchical porosity and damage-tolerant superhydrophobic properties simultaneously using divinylbenzene (DVB) and SiO₂ composites. The polymer monolith exhibiting a high specific surface area (820.5 m² g⁻¹) and large pore volume (1.59 cm³ g⁻¹) is obtained without using any fluorinated compounds, template, surfactant or stabilizer and further chemical modification which is green, low cost, simple and environmentally-safe. The hierarchical porosity of the polymer monolith is controllable readily by regulating the solvothermal temperature. In addition, the polymer monolith features excellent superhydrophobicity with a water contact angle of 161.3° and a sliding angle smaller than 4.0° as well as switchable wettability which can be realized by simple UV irradiation and abrasion. Importantly, the monolith demonstrates excellent mechanical resistance and environmental durability owing to its low-surface-energy microstructures extending throughout its whole volume which is comparable to most superhydrophobic surfaces that have poor durability. Moreover, the monolith can be used as a chalk for painting superhydrophobic porous polymer coating on substrates with various shapes and features, which facilitates the preparation of large area superhydrophobic surfaces and is extensively applicable.