Fabrication of highly efficient nano core–shell structure for the development of super-hydrophobic polymeric coating on mild steel

This research work deals with the development of a polymeric super-hydrophobic surface involving nano silica–titania core–shell particles. This core–shell structure enhanced the properties of two different materials in a single nanoparticle in an outstanding manner; polymeric coatings containing core silica and shell titania have improved the mechanical behavior and hydrophobicity of coating surfaces, respectively. This nano core–shell was synthesized through two different methodologies which were prepared at high and low processing temperature separately, that is, called sol–gel and peptization synthesis. Further surface properties of the prepared nanoparticles were investigated individually in solvent-based emulsions and water-based emulsions. Nanocoating formulations were developed on mild steel substrate for analysis on the mechanical behavior of the coating and contact angle measurement. In the coating formulation, nano core–shell concentrations ranged from 1% (wt) to 6% (wt), and used nanoparticles were functionalized with methyl trimethoxy silane for better surface properties. Based on the results of the experiment, core–shell nanocoatings have been found mechanically robust and superhydrophobic (∼145.1° ± 2°) coating.