Preparation of superhydrophobic polybenzoxazine/SiO2 films with self-cleaning and ice delay properties

Abstract Ice accumulation is a serious problem around the world, especially in cold regions. It is believed that a superhydrophobic surface has the potential to realize ice delay. Herein, we report an approach to fabricate superhydrophobic films combined with pendent aliphatic chain-substituted polybenzoxazine and silica nanoparticles (SiO 2 NPs) through spin coating and thermal curing. As a result, a superhydrophobic polybenzoxazine/SiO 2 film with a static water contact angle of 167 ± 2° and a water sliding angle of 5° was developed, which exhibits self-cleaning properties. The polybenzoxazine/SiO 2 film also exhibits ice delay properties owing to the decrease in the liquid-solid contact area and heat loss caused by air pockets under the micro-nano structure of the superhydrophobic film. Furthermore, the superhydrophobic polybenzoxazine/SiO 2 film retains its superhydrophobicity after heat treatment for 1 h within a wide temperature range. Moreover, the as-prepared superhydrophobic films are also stable over a wide pH range, from 1 to 14, or after UV exposure for 10 h.