Preparation and characterization of hydrophobic superparamagnetic magnetite gel

• Published in: Journal of magnetism and magnetic materials Vol. 306; no. 2; pp. 248 - 253
• Main Authors: Liu, Xianqiao, Kaminski, Michael D., Guan, Yueping, Chen, Haitao, Liu, Huizhou, Rosengart, Axel J.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.11.2006; Elsevier Science
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Diamagnetism, paramagnetism and superparamagnetism; Exact sciences and technology; FT-IR spectroscopy; Magnetic gel; Magnetic properties and materials; Magnetite; Physics; Preparation; Superparamagnetism; Superparamagnetism; Magnetite; FT-IR spectroscopy; Magnetic gel; Preparation; Particle size; Physical gel; Hydrophobic compound; Iron oxides; Microstructure; Saturation magnetization; Magnetic properties
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2006.03.049

The present study describes the preparation and analysis of a highly concentrated hydrophobic oleic acid-coated magnetite gel. By contrast to conventional techniques to prepare magnetic fluids, herein the oleic acid was introduced as a reactant during the initial crystallization phase of magnetite that was obtained by the co-precipitation of Fe(II) and Fe(III) salts by addition of ammonium hydroxide. The resulting gelatinous hydrophobic magnetite was characterized in terms of morphology, particle size, magnetic properties, crystal structure, and hydrophobicity/hydrophilicity. This magnetic gel exhibited superparamagnetism with a saturation magnetization of 46.0 emu/g at room temperature and could be well dispersed both in polar and nonpolar carrier liquids. This protocol produced highly concentrated hydrophobic magnetic gel for biopolymer encapsulations.