Improved thermooxidation and sedimentation stability of covalently-coated carbonyl iron particles with cholesteryl groups and their influence on magnetorheology

Miroslav Mrlík; Markéta Ilčíková; Vladimír Pavlínek; Jaroslav Mosnáček; Petra Peer; Petr Filip

doi:10.1016/j.jcis.2013.01.027

Improved thermooxidation and sedimentation stability of covalently-coated carbonyl iron particles with cholesteryl groups and their influence on magnetorheology

J Colloid Interface Sci. 2013 Apr 15:396:146-51. doi: 10.1016/j.jcis.2013.01.027. Epub 2013 Jan 31.

Authors

Miroslav Mrlík¹, Markéta Ilčíková, Vladimír Pavlínek, Jaroslav Mosnáček, Petra Peer, Petr Filip

Affiliation

¹ Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Zlin, Czech Republic. mrlik@ft.utb.cz

PMID: 23433972
DOI: 10.1016/j.jcis.2013.01.027

Abstract

Sedimentation of particles in magnetorheological suspensions represents a crucial problem that concerns their efficient long-term application in practice. Prepared carbonyl iron (CI) microparticles coated with a low density substance, cholesteryl chloroformate, via a two-step reaction and immersed in silicone oil, exhibit three positive aspects: (1) the CI particle modification increased the compatibility between the particles and the silicone oil resulting in improved long-term stability (reduction in sedimentation); (2) the coating provided the particles with enhanced thermal stability in the oxygen atmosphere; and (3) rheological measurements proved a promising magnetorheological performance at different particle weight fractions.