Synthesis and magnetic properties of a novel ferrite organogel

• Published in: Journal of applied physics 1999-04, Vol.85 (8), p.5965-5967
• Main Authors: Li, Sichu, John, Vijay T., Irvin, Glen C., Rachakonda, Suguna H., McPherson, Gary L., O’Connor, Charles J.
• Format: Article
• Language: English
• ISSN: 0021-8979; 1089-7550
• DOI: 10.1063/1.370006

A novel magnetic organogel that can be considered a precursor example of a magnetoresponsive gel is reported. The gel is formed by the bridging of ferrite containing anionic bis(2-ethlhexyl) sodium sulfosuccinate reverse micelles with 2,6-dihydroxynaphthalene (2,6-DHN). The addition of 2,6-DHN leads to a room temperature quotes “freezing in” of the liquid solution to a clear organogel. Ferrite particles in the size range 10–15 nm are doped into the gel network and are thus suspended in the optically clear gel media. The magnetic properties of the gel were measured using a superconducting quantum interference device magnetometer. The results reveal that the gel exhibits superparamagnetic behavior with a blocking temperature of 6 K (at an applied field of 1000 G), and a coercivity of 850 G at 2 K. The ferrites introduced into the gel serve the function of magnetic “seeds” via which magnetic properties are acquired by the gel.