A facile approach to fabricate bright blue heat-resisting paint with self-cleaning ability based on CoAl 2 O 4 /kaolin hybrid pigment

Abstract A bright blue and low-cost heat resisting paint with excellent self-cleaning ability was prepared by adding superhydrophobic CoAl2O4/kaolin hybrid pigment (K-HP). Kaolin (K) was served as a suitable matrix for anchoring CoAl2O4 nanoparticles to prepare K-HP, and then it was modified with hexadecyltrimethoxysilane to construct the superhydrophobic hybrid pigment based on the rough structure of K-HP. The sprayed coating of the superhydrophobic heat-resisting paints exhibited the good self-cleaning performance with high water contact angle of 164.3 o and low sliding angle of 1.2 o below 380 °C, as well as the excellent color properties (L*= 41.72, a* = − 3.01, b* = − 62.93) and thermal stability even at 800 °C. Incorporation of K-HP not only improves the thermal stability of the heat-resisting paint, but also effectively protects steel plate substrate from damage during the calcining process. Therefore, it is expected to provide a facile approach to fabricate the chromatic self-cleaning heat-resisting paint with excellent thermal stability.