Methyltriethoxysilane modified nano-alumina sol to fabricate organic/inorganic hybrid refractory coating

Abstract

The development of refractory coating with dense surface and excellent fire resistance is an urgent need in practical application. Herein, an organic/inorganic hybrid refractory coating containing methyltriethoxysilane modified nano-alumina sol was fabricated. The film-forming ability of the coating materials was significantly improved via the hybridization reaction between methyltriethoxysilane and nano-alumina sol. The effect of the ratio of methyltriethoxysilane to nano-alumina sol on the performance of the coatings was thoroughly explored. The results showed that the mechanical property of the coating increased while the flame retardancy slightly decreased with the increase of the molar ratio of methyltriethoxysilane and aluminum sol. The comprehensive performance of the hybrid coating was best when the molar ratio of aluminum sol and methyltriethoxysilane was about 1:3 (R1-M3). The coating that sprayed on the clean aluminum alloy panels demonstated high rigidity (4 H), excellent adhesion (5B) and good impact resistance (50 cm). Furthermore, the organic/inorganic hybrid coating of R1-M3 shown smooth and dense surface and exhibited excellent fire resistance. It was observed that the residual weight at 900 °C was as high as 82.18%.