Chemical modification of Fe powders under surfactant-assisted ball milling in polydiene solutions

Abstract

Composite materials are of great importance for both science and technology. In this work, the high-energy ball milling of carbonyl iron in the presence of polydienes of various structures (cis-polybutadiene, cis- and trans-polyisoprene) and surfactants (perfluorononanoic and stearic acid) is used to chemically modify the bulk and surface of iron particles. A comprehensive study of the particles was performed with the use of various experimental techniques. Mechanochemically activated iron surface favors the processes of decomposition and transformation of organic molecules that make up the milling medium, resulting in the accumulation of carbides in the particles bulk and the formation of modified organic layer on the surface. The composition and thickness of the modified layer as well as the arrangement of organic molecules in it was shown to be sensitive to variations in the chemical structure of the initial diene polymer and the type of surfactant added. The as-grown layers inhibit corrosive destruction of the resulting particles. Platelet-shaped particles prepared by surfactant-assisted ball milling can be used as fillers for magnetodielectric composites with high permittivity and permeability values.