%0 Journal Article
%T Depercolation of aggregates upon polymer grafting in simplified industrial nanocomposites studied with dielectric spectroscopy
%+ Centre de Technologie de Ladoux
%+ Laboratoire Charles Coulomb (L2C)
%+ Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU)
%+ Martin-Luther-Universität Halle Wittenberg (MLU)
%A Baeza, Guilhem
%A Oberdisse, Julian
%A Alegria, Angel
%A Saalwaechter, Kay
%A Couty, Marc
%A Genix, Anne-Caroline
%< avec comité de lecture
%Z L2C:15-149
%@ 0032-3861
%J Polymer
%I Elsevier
%V 73
%P 131-138
%8 2015
%D 2015
%R 10.1016/j.polymer.2015.07.045
%K Nanocomposites
%K Dynamics
%K Polymer grafting
%K Percolation
%Z Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft]
%Z Chemical Sciences/PolymersJournal articles
%X The dynamics of polymer and filler in simplified industrial silica-styrene-butadiene nanocomposites (silica Zeosil 1165 MP, volume fraction 0 – 21%v) have been studied with broadband dielectric spectroscopy (BDS) and nuclear magnetic resonance (NMR). The fraction of graftable matrix chains was varied from 0 – 100%D3. The introduction of silica nanoparticles is shown to leave the segmental relaxation unaffected, an observation confirmed by the measurement of only a thin (some Angstroms thick) immobilized layer by NMR. The low-frequency measurements are resolved in two distinct dielectric Maxwell-Wagner-Sillars (MWS) processes of different behavior with respect to changes of large-scale silica structures induced by variations of filler fraction and grafting. In particular, depercolation of the silica filler at constant volume fraction with increasing grafting leaves the first MWS-process unaffected, but has direct consequences on rheological reinforcement, and decreases the strength of the second MWS by about a decade. This sensitivity to large-scale reorganizations together with a characterization of local polymer dynamics provides insight over many length- and time-scales into structure and dynamics of nanocomposites, and thus the physical origin of the reinforcement effect. 
%G English
%2 https://hal.science/hal-01201618/document
%2 https://hal.science/hal-01201618/file/dielectric%2520spectroscopy.pdf
%L hal-01201618
%U https://hal.science/hal-01201618
%~ CNRS
%~ L2C
%~ MIPS
%~ UNIV-MONTPELLIER
%~ UM-2015-2021