Quantification of Nanocomposite Dispersion for Weakly Correlated Systems*

Nanocomposites such as carbon black dispersions in elastomers can be describe by a mean-field approach and the RPA equation. [1,2] However, dispersion of nanoparticles influenced by surface potentials or entropic and steric interactions, such as for surface-grafted nanoparticles, often cannot be described using the mean-field approach since the particles are weakly organized. For these cases it is necessary to consider a discrete correlation function and an associated structure factor in scattering. Recently Oberdisse and Genix [3] have developed an approach to model scattering from nanocomposites of precipitated silica in elastomers. In this talk an approach similar to Oberdisse is used but with a simpler structure factor based on the Born-Green approach of Guinier and Fournet. [4] The result is a simple parameterization of correlations that can be used to determine the second virial coefficient for direct comparison with uncorrelated systems such as fumed silica or carbon black in elastomers.
1 Vogtt, K. et al. Soft Matter 2017.
2 Pedersen, J. S. et al. Progr Colloid Polym Sci 2005, 130, 70–78.
3 Baeza, G. P. et al. Macromolecules 2013, 46 (1), 317–329.
4 Guinier, A.; Fournet, G. Small-Angle Scattering Of X-Rays; John Wiley & Sons, 1955.