Self-assembly of organophilic nanoparticles in a polymer matrix: Depletion interactions
Journal
Journal of Physical Chemistry C
Journal Volume
116
Journal Issue
2
Pages
1789-1797
Date Issued
2012
Author(s)
Abstract
The dispersion of nanoparticles in a polymer matrix has been proven a challenge. A recent experiment reveals that it can be controlled by the relative size of nanoparticle/matrix polymer instead of their compatibility. Dissipative particle dynamics simulations are thus employed to investigate self-assembly of organophilic nanoparticles and dispersion of organophobic nanoparticles. The degree of aggregation in terms of the mean aggregation number is evaluated to explore the aggregation kinetics of nanocubes and nanoplatelets. The influence of the length of the matrix polymer on the aggregation behavior is studied as well. It is found that the depletion attraction plays the major role for the aggregation of organophilic nanoparticles. Large nanoplatelets prefer clustering, while small nanoplatelets tend to disperse because the depletion attraction grows with the face area of nanoparticles. On the other hand, the slow aggregation kinetics, hindered by the energy barrier associated with depletion interactions and low nanoparticle diffusivity, is responsible for the low degree of aggregation for organophobic nanoparticles.
SDGs
Type
journal article