ma4008626_si_001.pdf (2.21 MB)
RAFT-Polymers with Single and Multiple Trithiocarbonate Groups as Uniform Gold-Nanoparticle Coatings
journal contribution
posted on 2013-06-25, 00:00 authored by Bastian Ebeling, Philipp VanaThe nanostructures of nanohybrids
with gold-nanocrystal cores and
shells of N-isopropylacrylamide polymers containing
single or multiple trithiocarbonate (TTC) groups were analyzed in
detail. The polymers were synthesized in RAFT polymerizations and
then grafted to gold nanoparticles (∼14 nm) from citrate reduction.
Analysis via TEM revealed self-assembled hexagonal lattices of gold
cores. The interparticle distances increased, when polymers with single
TTC end groups and growing molar masses were employed as coating agents,
allowing for a reference curve to be found. When using polymers containing
multiple TTC groups along their backbone for the surface modification,
the spacings between the gold cores were unexpectedly low and remained
constant, independent of the polymers’ chain lengths and the
number of trithiocarbonate groups, which showsbacked up by
results from size-exclusion chromatographythat these macromolecules
are wrapped around the gold nanoparticles with several gold–TTC
junctions. Absolutely no cross-linking was observed for these novel
and promising nanohybrids.