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allied
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Materials-Metals 2017
Page 51
November 16-17, 2017 Paris, France
13
th
Annual Conference on
Materials Science, Metal and Manufacturing
Journal of Materials Science and Nanotechnology
Volume 1 Issue 2
Iron Oxide-Polymer brush nanocomposites
with switchable adsorption properties toward
methylene blue
Lee D. Wilson and Asghar Dolatkhah
University of Saskatchewan, Canada
T
he grafting from approach was used to prepare pH-
responsive polyacid brushes using poly(itaconic acid)
(PIA) and poly(acrylic acid) (PAA) at the amine functional
groups of chitosan. Hybrid materials consisting of polymer
brushes and magnetite nanoparticles (MNPs) were also
prepared. The products were structurally characterized
and displayed reversible pH-responsive behavior and
controlled adsorption/desorption of methylene blue (MB).
Switchable binding of MB involves cooperative effects due to
conformational changes of brushes and swelling phenomena
in solution which arise from response to changes in pH. Above
the pKa, magnetic nanocomposites (MNCs) are deprotonated
and display enhanced electrostatic interactions with high MB
removal efficiency (>99%). Below the pKa, MNCs undergo
self-assembly and release the cationic dye. The switchable
binding of MB and the structure of the polymer brush
between collapsed and extended forms relate to changes in
osmotic pressure due to reversible ionization of acid groups at
variable pH. Reversible adsorption–desorption with variable
binding affinity and regeneration ability was demonstrated
after five cycles. Additional examples of recent studies on
the design and physicochemical properties of polymer-metal
composites will be described in this presentation.
lee.wilson@usask.caMater Sci Nanotechnol 2017, 1:2