Optimised silica-based hybrid coatings for the protection of aluminum

Chemists have studied silica-based hybrid coatings for the protection of aluminum against chloride-rich environment.

Sol–gel hybrid coatings have become one of the dominant platforms intended for anticorrosion applications. In a new study, hybrid (silica/epoxy) ceramic coatings were designed and prepared using the sol–gel technique.

3-Glycidyloxypropyl trimethoxysilane and diglycidyl ether of bisphenol A (epoxy) were used as the main precursors, while 3-Aminopropyl triethoxysilane was involved as a coupling agent (linker) in different ratios along with diethylenetriamine as a tertiary hardener responsible for the hybrids curing.

Improvements could be witnessed by increasing the silica content
It was proven that the morphology of the product would vary in a great deal depending on the silica content, which plays a vital role in determining the mechanical and thermal properties of these coatings. Improvements could be witnessed by increasing the silica content up to a specific limit (ranging from 15 to 20%). However, a further increase in the silica content will lead to a noticeable drop in the corrosion resistance capability.