Robust superhydrophobicity by candle soot deposition on plasma-treated PETG

Abstract

Surface etching was achieved by exposing poly(ethylene glycol-co-1,3/1,4 cyclohexanedimethanol terephthalate) (PETG) samples to oxygen plasma produced in reactive-ion etching configuration of a radiofrequency plasma device. The surface modifications on the sample surfaces were determined by employing water contact angle measurements and profilometry. Enhanced wettability was observed for the plasma-treated samples together with a general increase in the surface roughness for the plasma-treated samples as compared to the control samples due to surface etching. Superhydrophobic candle soot coatings with a maximum water contact angle of 164° were deposited on the control and plasma-treated samples. Durability tests such as water and ethanol immersions were performed on the samples with the results demonstrating that samples with higher surface roughness values exhibited better candle soot coating adhesion to the PETG samples.