Langevin Dynamics Prediction of Polymer-Particle Adsorption and Saturation Processes in Shear Flows

Polymer-particle interactions, adsorption and subsequent polymer saturation in shear flows is studied using Langevin dynamics and a potential-based interaction modelling technique. The polymeric phase is modelled as macromolecular chains of interacting beads (monomers), with the effects of bead-bead and bead-particle steric interactions incorporated through a truncated Lennard-Jones potential and the Kratky-Porod bending rigidity accounted for. Simulations of multi-polymer particle adsorption events are performed, with the effects of bending rigidity studied. It is found that for low bending rigidities, polymers fully adsorb onto the particle, with conformities tightly bound and flattened to the spherical surface. Increased rigidities cause polymer chains to hang away from the particle surface. Around 75% adsorption is achieved for low rigidity polymers whereas for high rigidity, just over half of the monomers remain bound. Furthermore, it is demonstrated that increasing the rigidity leads to more monomers present in the surrounding area adsorption zone, constituting an increase in effective radius.