polymer nanocomposite

Mechanisms of reinforcement in polymer nanocomposites

N. Molinari, A. P. Sutton and A. A. Mostofi, Mechanisms of reinforcement in polymer nanocomposites, Phys. Chem. Chem. Phys. 20, 23085 (2018)

Nanoparticles of carbon or silica, for example, are routinely added to polymers during their processing to tune the mechanical and chemical properties of the polymer. Such systems are known as polymer nanocomposites. In this work, which appears in Phys. Chem. Chem. Phys. this week, we have uncovered some of the molecular mechanisms that govern the mechanical strengthening of polymer nanocomposites. Using coarse-grained molecular dynamics simulations, we find that the mechanical response to tensile strain depends systematically on the fraction of the total volume of the nanocomposite that is occupied by the nanoparticles. We identify three predominant local structural motifs that are present at the molecular level and we show how and why the evolution of the these motifs with the concentration of nanoparticles and with strain governs the mechanical response.

This work was part of Nicola Molinari’s PhD in the Centre for Doctoral Training in Theory and Simulation of Materials. Nicola was supervised by Adrian Sutton and Arash Mostofi.