Influence of the shape of silica nanoparticles on the elastic properties and glass transition temperature of PLA-based nanocomposites: Molecular dynamics simulation

In this study, the influence of shape of silica nanoparticles (SiO 2 ) on the thermal and mechanical properties of polymer-based composites was analysed using the molecular dynamics method in LAMMPS software. The matrix of all atomic samples was polylactic acid (PLA) and SiO 2 particles, with various shapes including rod, and, wire shapes were used as reinforcements. All samples’ modulus of elasticity, Poisson's ratio and glass transition temperature ( T g ) values were calculated separately after equilibrium and applying the constant-temperature, constant-volume ensemble (NVT). The results of the simulations showed that the spherical shape of SiO 2 nanoparticles has the greatest effect on the modulus of elasticity with an increase of 232% compared to pure PLA. The rod shape of SiO 2 nanoparticles had the greatest effect in reducing the T g of pure PLA with a reduction of 24%. Regarding Poisson's ratio, the spherical shape of SiO 2 nanoparticles had the greatest effect with an increase of 48%.