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Structural Analysis. Impact of the filler fraction in NCs. G. Baeza et al. Macromolecules 2013 Multi-scale filler structure in simplified industrial nanocomposite systems silica/SBR studied by SAXS and TEM. Multiscale Structure. network. aggregates. beads. R bead 10 nm. q -2.4.
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Structural Analysis • Impact of the filler fraction in NCs G. Baeza et al. Macromolecules 2013 Multi-scale filler structure in simplified industrial nanocomposite systems silica/SBR studied by SAXS and TEM
Multiscale Structure network aggregates beads Rbead10 nm q-2.4 Artistview Tridimensionnal network built up from aggregates made of nanoparticles Ragg40 nm dbranch120 nm • si (Quantitative Model) • Densification of the silica network • Aggregates remain similar
Global View: 3-level Organization analysis network aggregate bead High-q : Bead form factor qsi Rsi (R0= 8.55 nm = 27%) Medium-q : qagg Ragg (35 – 40 nm) Interactions Between Aggregates Low-q : qbranch Network branches (lateral dimension 150 nm), compatible with fractal aggregates (d2.4). The network becomes denser and denser with si Artist view: network built up from Aggregates made of nanoparticles
Quantitative analysis: Aggregate Radius Subtraction of the fractal law Kratky Plots allow to extract <Ragg> qagg d 2.4 si qagg Morphology of an aggregate Ragg Distribution Hypothesis Ragg
Quantitative model Scattering law linking structure and form (polydisperse case) 1) Determination of <Pagg> Ragg distribution Nagg distribution Working hypothesis * Calculation *Oberdisse, J.; Deme, B. Macromolecules 2002, 35 (11), 4397-4405
Quantitative model Scattering law linking structure and form (polydisperse case) Sapp (q) depends on local si in the branches = agg inter app 2) Determination of Sinter(q) • Estimation of agg: TEM Same Working hypothesis fract • Monte Carlo Simulation of polydisperse aggregates Hard-SpherePotential (PY like) agg Semi-Empiriclaw from simulation
Self Consistent Model • Final determination of I(q) is read Experimental I(q) = f() saxs Results: <Ragg> decreases slightly increases slightly <Nagg> constant !