Superparamagnetic Nanocomposites Based On Poly(styrene-b-ethylene/butylene-b-styrene)/Cobalt Ferrite Compositions
Document Type
Article
Publication Date
4-1-2006
Department
Polymers and High Performance Materials
Abstract
Magnetic nanoparticles were created in or around the sulfonated (s) polystyrene domains in a phase separated poly[styrene-b-(ethylene-co-butylene)-b-styrene)] block copolymer (BCP) using an in situ inorganic precipitation procedure. The sBCP was neutralized with a mixed iron/cobalt chloride electrolyte and the doped samples were converted to their oxides by reaction with sodium hydroxide and further washing with water. Transmission electron microscopy indicated the presence of nanoparticles in the 5-25 nm size range. The metal oxide particle structures were studied using select area electron diffraction, which revealed that they are of the cobalt iron oxide composition (CoFe2O4). These nanocomposites were shown, using a superconducting quantum interference device magnetometer, to be superparamagnetic at 300 K and ferrimagnetic at 5 K. Nanocomposites consisting of smaller particles have a blocking temperature of 70 K, whereas it was 140 K for larger particles. (C) 2005 Elsevier B.V. All rights reserved.
Publication Title
Journal of Magnetism and Magnetic Materials
Volume
299
Issue
1
First Page
211
Last Page
218
Recommended Citation
Rajan, G. S.,
Stromeyer, S. L.,
Mauritz, K. A.,
Miao, G.,
Mani, P.,
Shamsuzzoha, M.,
Nikles, D. E.,
Gupta, A.
(2006). Superparamagnetic Nanocomposites Based On Poly(styrene-b-ethylene/butylene-b-styrene)/Cobalt Ferrite Compositions. Journal of Magnetism and Magnetic Materials, 299(1), 211-218.
Available at: https://aquila.usm.edu/fac_pubs/2404