Self-replenishing superhydrophobic durable polymeric nanocomposite coatings for heat exchanger channels in thermal management applications

We developed two-coat polymeric nanocomposite coatings for the protection of steel structures from the thermal and corrosive environment. To protect the steel structures, the coating selectivity is crucial; we have chosen the coating such way, the coated surface has low surface energy polymer which has low surface polarity. The polymer nanocomposite coatings were prepared using polydimethylsiloxane with an optimal amount of zirconia nanoparticle. The incorporation of zirconia nanoparticle has extended the thermal stability and efficient corrosion protection of steel substrates. The formulated coatings exhibited a superhydrophobic characteristic with CA-165 degrees and low contact angle hysteresis (< 5 degrees). The present study focuses more on the robust superhydrophobic behaviour, were studied using the effectiveness of underwater stability over 30 days in static immersion and water impingement analysis with a velocity of 7.302 m/s at continuous exposure. PDMS-ZrO2 composite films showed excellent resistance to different pH stress without loss of coating. The chemical composition and microstructure of the coatings were studied using EDX and SEM, respectively. The predictive life of the coating performance has been further evaluated by pool boiling test, Thermal shock test, and Electrochemical Impedance Spectroscopy.