Formation, characterization and protective properties of organic/silicate hybrid shells on flaky Fe-Si-Al particles obtained by wet ball milling

Abstract In this study a facile approach is proposed to fabricate flaky Fe-Si-Al particles covered with organic molecules of various types, including organosilicon linear-ladder block copolymer, surfactants (sodium dodecyl sulfate, stearic acid) and corrosion inhibitor (N-phenylanthranilic acid) as well as their combinations. The proposed method involves conventional ball milling of Fe-Si-Al alloy in organic liquids with desired modifiers which provides the formation of organic/silicate hybrid shells on the particles surface. XPS and FTIR analysis of the prepared particles clearly show that organic molecules are grafted onto their surface layers composed of aluminum and iron silicates. Different modifying agents are demonstrated to bind with different atoms of the oxide shells, with organosilicon copolymer being attached to silicon-oxygen tetrahedra, and carboxylic acids forming adsorption carboxylate complexes with metal atoms. Combined modifiers give mixed organic layers which turn out to be thinner as compared to those formed with only one modifier. The better anticorrosive effect is observed for mixed layers composed of organosilicon copolymer and N-phenylanthranilic acid.