UNDERSTANDING THE EFFECT OF SHEAR ON POLYMER AGGREGATES BY USING MOLECULAR DYNAMICS SIMULATION

Abstract

This study uses comprehensive molecular dynamics (MD) simulations to investigate the effects of shear on the dynamics and structural characteristics of polymer aggregates. For polymer aggregates, we specifically study the relationship between shear stress, radius of gyration (Rg), and time under a variety of conditions, such as different interaction strengths (𝜀 = 1, 5, 10), spring constants (𝑘 = 0.1, 1, 10), chain lengths (80, 100, 120 beads per chain), concentration (4000, 5000, 6000 beads in the same volume), and shear rates (0.008,0.08, 0.8). Non-equilibrium molecular dynamics (NEMD) methods are used in the simulations to replicate realistic shear conditions. Based on varying shear rates and material parameters, our findings show substantial differences in the stress response and structural changes of the polymer chains with variation in the model parameters. The mechanical stability and deformation behaviour of polymer-based systems are fundamentally understood by these studies, and this understanding is essential for optimising the systems' performance in applications like drug delivery. In addition to providing guidance for the design of strong polymer aggregates with improved stability and regulated drug release characteristics under mechanical stress, the work lays the foundation for future research on the impacts of shear on intricate polymer systems.