Durable superhydrophobic EVA cellular material spin-coated by SiO2/SEBS-g-MAH toward self-cleaning roofs

Ethylene-vinyl acetate copolymer (EVA) cellular material as one of important porous materials has been employed in the fields of outdoors cushioning. However, studies toward the construction of superhydrophobic structures on its surface for outdoor hygiene remains inadequate. In this work, a series of durable superhydrophobic SiO2/maleic anhydride grafted styrene-ethylene-butylene-styrene (SEBS-g-MAH) coatings with different weight contents of SiO2 were spin-coated on EVA cellular material's surface. 5Si-5S (50 wt% SiO2 and 50 wt% SEBS-g-MAH) coating showed water contact angle (WCA) of 162 degrees and sliding angle of 6.3 degrees. Meanwhile, 5Si-5S surface exhibited significant self-cleaning, anti-fouling and long-term water impact resistance abilities. Compared with Control sample, a freezing delay time of similar to 120 s and the 0.86 N reduction of ice adhesion force can also be realized. Contact angle values of 5Si-5S surface fluctuated around 160 degrees as the pH of droplet changed in the range of pH 2-13. Moreover, the adhesive rate can reach 4B according to the ASTM D3359 and WCA can remain 150 degrees after sandpaper abrasion, indicating its durability of hydrophobicity. The as-prepared EVA cellular material with durable superhydrophobic coating was expected as an outdoor building roof material toward selfcleaning and anti-icing application.

Automated summary

In this study, durable superhydrophobic coatings were spin-coated on the surface of EVA cellular material, demonstrating self-cleaning and anti-icing properties for outdoor applications.