Impalement-resistant and robust superhydrophobic umbrella fabric enabled by a similar “pole erecting” strategy

Abstract

Superhydrophobic coatings for umbrella canopies have the potential to solve the issue of rain residue. However, achieving both impalement resistance and mechanical robustness in these coatings poses a significant challenge and limits their practical applications. In this study, we propose a similar “pole erecting” method utilizing perfluorodecyl polysiloxane modified SiO2 nanoparticles (F-silica) as the pole and poly(dimethylsiloxane) (PDMS) as the screw to enhance impalement resistance and mechanical robustness, which is attributed to the three-tier hierarchical micro-/micro-/nanostructure bonded by PDMS, along with a reduction in aspect ratio. The obtained PDMS0.5-F-silica could withstand 150 min of water drop impacting (equivalent to approximately 19,000 water drops) and 60 s of 50 kPa water jetting, also showed exceptional endurance against various mechanical tests, including 200 cycles of reciprocating abrasion, 1000 cycles of Martindale abrasion and 200 cycles of tape peeling. Moreover, when applying the PDMS0.5-F-silica coating to umbrella canopies, we observed an absence of rain residue after subjecting the umbrella to 20 h rain. These findings are promising for the development and practical implementation of superhydrophobic coatings.