Icephobic properties of aqueous self-lubricating coatings containing PEG-PDMS copolymers

Icephobic coatings offer an effective solution for protecting infrastructures subjected to harsh cold-weather environments. Aqueous self-lubricating coatings, derived from the principles of ice skate sliding over ice, provide a cost-effective anti-icing method. Here, we fabricate aqueous self-lubricating coatings by adding polydimethylsiloxane-poly (ethylene glycol) (PEG-PDMS) copolymers to a PDMS matrix. We analyzed the wettability, morphology, and topography of the fabricated coatings using a goniometer, scanning electron microscopy (SEM), and atomic force microscopy (AFM), respectively. Differential scanning calorimetry (DSC), push-off and centrifugal tests detailed the icephobic characteristics of the coating surfaces. Blending PEG-PDMS into the elastomeric matrix enhanced the effective contact area between the water droplet and the coating; the formation of hydrogen bonds between water molecules and the hydrophilic functional groups of the coating produced this effect, and water molecules spread readily over the surface. Increased concentrations of these functional groups increased the freezing-delay time and reduced ice adhesion strength, likely owing to the formation of a quasi-liquid-like layer. Nonetheless, the immiscibility of the PEG-PDMS copolymer within the PDMS matrix can negatively affect wettability and the icephobic characteristics of the coatings. An optimized copolymer content of 5% produced a durable icephobic aqueous self-lubricating coating.

Automated summary

Icephobic coatings offer protection for infrastructures in cold environments. Aqueous self-lubricating coatings, fabricated by blending PEG-PDMS into a PDMS matrix, enhance contact area, forming hydrogen bonds and quasi-liquid-like layers to reduce ice adhesion strength and delay freezing. Optimized copolymer content of 5% produces durable icephobic coatings.