Facile method to convert petal effect surface to lotus effect surface for superhydrophobic polydimethylsiloxane

The present study uses a facile method to produce a superhydrophobic polydimethylsiloxane (PDMS) surface with sandpaper molding and convert it from petal effect surface to lotus effect surface. This process increases the water contact angle (WCA) from 116.4 degrees to 150.3 degrees. The sandpaper-molded PDMS exhibits high adhesion for water droplets, that is, it has a petal effect surface. With perfluorodecyltrichlorosilane (PFDTS) solution immersion treatment of the PDMS, the contact angle hysteresis (CAH) reduces from 20.3 degrees to 8.2 degrees as the sliding angle (SA) reduces to 4, that is, it has a lotus effect surface. This study presents a facile method to convert a petal effect surface to a lotus effect one for a rough PDMS surface. The chemical stability of fluorocarbons was tested in a solvent bath with 10 min ultrasonication. The results show that PFDTS can be grafted on sandpaper-molded PDMS surfaces without plasma pretreatment.

Automated summary

This study uses a simple method to produce a superhydrophobic PDMS surface and convert it from a petal effect to a lotus effect surface. By treating PDMS with PFDTS solution, the contact angle hysteresis is significantly reduced, resulting in a lotus effect surface. This study provides a convenient method to transform a rough PDMS surface into a lotus effect surface.