TY  - JOUR
AU  - Glomann, Thomas
AU  - Hamm, Adrian
AU  - Allgaier, Jürgen
AU  - Hübner, Eike G.
AU  - Radulescu, Aurel
AU  - Farago, Bela
AU  - Schneider, Gerald Johannes
TI  - A microscopic view on the large scale chain dynamics in nanocomposites with attractive interactions
JO  - Soft matter
VL  - 44
IS  - 9
SN  - 1744-6848
CY  - Cambridge
PB  - Royal Society of Chemistry (RSC)
M1  - FZJ-2013-03994
SP  - 10559-10571
PY  - 2013
N1  - Creative Commons Licence CCBYNC
AB  - We use neutron spin-echo spectroscopy to investigate the large scale chain dynamics in unentangled polymer nanocomposites where stable polymer layers around nanoparticles are dynamically formed due to attractive segment–surface interactions. The work here focuses on the detailed microscopic characterization of the dynamics within these layers of bound poly(ethylene glycol) (PEO) and poly(butylene oxide) (PBO) chains at a fixed silica nanoparticle fraction of 15%. The substitution of hydroxy by methoxy terminated chains thereby clearly evidences the importance of the chain end chemistry in these systems as the layer structure and dynamics therein significantly depend on the specific interaction mechanism. The experimental data reveal a densely packed thick shell of end-attached chains in the case of hydroxy ends contrasted by a thin shell of laterally adsorbed chains with multiple attachments in the methoxy case. In all cases a consistent quantitative modeling is presented that evidences unchanged segmental dynamics within the bound layers. The obtained picture is further validated on an independent model system based on PBO polymers which shows surprisingly similar chain dynamics as for PEG in the nanocomposite pointing to a very generic dynamic scenario.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000326287700014
DO  - DOI:10.1039/c3sm51194d
UR  - https://juser.fz-juelich.de/record/137614
ER  -