Preparation of Polymer Brush Grafted Anionic or Cationic
Silica Nanoparticles: Systematic Variation of the Polymer Shell
Marek Sokolowski
Christoph Bartsch
Vivian J. Spiering
Sylvain Prévost
Marie-Sousai Appavou
Ralf Schweins
Michael Gradzielski
10.1021/acs.macromol.8b01019.s002
https://acs.figshare.com/articles/journal_contribution/Preparation_of_Polymer_Brush_Grafted_Anionic_or_Cationic_Silica_Nanoparticles_Systematic_Variation_of_the_Polymer_Shell/7024724
Polymer
brush grafted anionic SiO<sub>2</sub>@PMAA (poly(methacrylic
acid)) and cationic SiO<sub>2</sub>@PDMAEMA (poly(2-(dimethylamino)ethyl
methacrylate)) inorganic/polymer hybrid nanoparticles with different
core radii (<i>d</i><sub>NP</sub> = 50–140 nm) and
different amounts of attached polymer were synthesized via surface-initiated
atomic transfer radical polymerization (ATRP). To avoid irreversible
aggregation, a three-step surface modification had to be employed,
thereby keeping the nanoparticles always dispersed. For SiO<sub>2</sub>@PMAA the shell thickness changes with the monomer concentration,
while for SiO<sub>2</sub>@PDMAEMA the grafting density was changed
by monomer concentration and the shell thickness remained constant.
We assume that the control over the grafting density relies on the
nature of the complexation potential of the PDMAEMA. The structural
characterization of the polymer grafted SiO<sub>2</sub>-NPs was done
in detail by different scattering methods combined with thermogravimetric
analysis, and details of the brush characteristics are obtained by
small-angle neutron scattering (SANS). With this approach we were
able to produce silica nanoparticles with anionic and cationic polymer
shells, where the softness of the NPs can be controlled by the amount
of polymer, which are pH-responsive and colloidally stable over a
large pH range.
2018-08-29 17:53:16
Cationic Silica Nanoparticles
nanoparticle
PDMAEMA
cationic SiO 2
NP
SANS
monomer concentration
Polymer Brush Grafted Anionic
cationic polymer shells
SiO 2
PMAA
density
shell thickness changes
Polymer Shell Polymer brush
ATRP