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Title: Preparation and characterization of hydrophobic superparamagnetic gel.

Abstract

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.

Authors:
; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOD; OUS
OSTI Identifier:
939308
Report Number(s):
ANL/CMT/JA-55941
Journal ID: ISSN 0304-8853; JMMMDC; TRN: US200823%%76
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Magn. Magn. Mater.; Journal Volume: 306; Journal Issue: 2006
Country of Publication:
United States
Language:
ENGLISH
Subject:
36 MATERIALS SCIENCE; AMMONIUM HYDROXIDES; CRYSTAL STRUCTURE; CRYSTALLIZATION; MAGNETIC PROPERTIES; MAGNETITE; MAGNETIZATION; MORPHOLOGY; OLEIC ACID; PARTICLE SIZE; SATURATION; SUPERPARAMAGNETISM

Citation Formats

Liu, X., Kaminski, M. D., Guan, Y., Chen, H., Liu, H., Rosengart, A. J., Chemical Engineering, Univ. of Chicago, Pritzker School of Medicine, and Chinese Academy of Sciences. Preparation and characterization of hydrophobic superparamagnetic gel.. United States: N. p., 2006. Web. doi:10.1016/j.jmmm.2006.03.049.
Liu, X., Kaminski, M. D., Guan, Y., Chen, H., Liu, H., Rosengart, A. J., Chemical Engineering, Univ. of Chicago, Pritzker School of Medicine, & Chinese Academy of Sciences. Preparation and characterization of hydrophobic superparamagnetic gel.. United States. doi:10.1016/j.jmmm.2006.03.049.
Liu, X., Kaminski, M. D., Guan, Y., Chen, H., Liu, H., Rosengart, A. J., Chemical Engineering, Univ. of Chicago, Pritzker School of Medicine, and Chinese Academy of Sciences. Sun . "Preparation and characterization of hydrophobic superparamagnetic gel.". United States. doi:10.1016/j.jmmm.2006.03.049.
@article{osti_939308,
title = {Preparation and characterization of hydrophobic superparamagnetic gel.},
author = {Liu, X. and Kaminski, M. D. and Guan, Y. and Chen, H. and Liu, H. and Rosengart, A. J. and Chemical Engineering and Univ. of Chicago and Pritzker School of Medicine and Chinese Academy of Sciences},
abstractNote = {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.},
doi = {10.1016/j.jmmm.2006.03.049},
journal = {J. Magn. Magn. Mater.},
number = 2006,
volume = 306,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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