1 research outputs found
Aggregate Formation of Surface-Modified Nanoparticles in Solvents and Polymer Nanocomposites
A new
method based on the combination of small-angle scattering,
reverse Monte Carlo simulations, and an aggregate recognition algorithm
is proposed to characterize the structure of nanoparticle suspensions
in solvents and polymer nanocomposites, allowing detailed studies
of the impact of different nanoparticle surface modifications. Experimental
small-angle scattering is reproduced using simulated annealing of
configurations of polydisperse particles in a simulation box compatible
with the lowest experimental <i>q</i>-vector. Then, properties
of interest like aggregation states are extracted from these configurations
and averaged. This approach has been applied to silane surface-modified
silica nanoparticles with different grafting groups, in solvents and
after casting into polymer matrices. It is shown that the chemistry
of the silane function, in particular mono- or trifunctionality possibly
related to patch formation, affects the dispersion state in a given
medium, in spite of an unchanged alkyl-chain length. Our approach
may be applied to study any dispersion or aggregation state of nanoparticles.
Concerning nanocomposites, the method has potential impact on the
design of new formulations allowing controlled tuning of nanoparticle
dispersion