Fly ash in superhydrophobic coatings
Fly ash (FA) is an industrial solid waste which adds burden to the environment. A new paper proposes a novel and facile way to reutilise varisized FA particles to prepare superhydrophobic coatings which exhibit excellent water-repellency and mechanical wear resistance. The FA particles undergo chemical modification (MFA), then physically mixing with polydimethylsiloxane (PDMS), and finally spraying or dipping to obtain the nano/micro, nano-micro, and nano-micro-submillimeter hydrophobic/superhydrophobic surfaces (MFA@PDMS) on versatile substrates.
Superhydrophobic even after abrasion
The results of SEM, FITR and contact angle indicate that the surface of FA was roughened after modification and the wettability of MFA particles transferred from hydrophilic to hydrophobic. The prepared nano-micro MFA@PDMS coating remains superhydrophobic even after 60 times unidirectional abrasion under 500 g weight, due to the fact that the presence of polydimethylsiloxane enhanced the binding force between inter-particles as well as particle-substrate.
The study has been published in Progress in Organic Coatings, Volume 176, March 2023.