Molecular Dynamics Simulation of Single Chain in the Vicinity of Nanoparticle

Abstract

Molecular simulation of single chain in the vicinity of nanoparticle in comparison with pure system is presented. According to the Rouse theory, chains were considered as a sequence of beads connected together by harmonic springs. The motion of atoms was supported by thermal energy and retarded by the resistance of surrounding. New atom position, in given time, was determined by the Smoluchowski equation, that consists of two terms: first one includes the influence of the inter-atomic collisions, the sterical obstacles and the strong intermolecular interactions in friction coefficient, second one express the energy field aggregated from potentials of all atoms. Sinusoidal shear stress was applied to the chain. The output of the model was energy as a function of time. The energy course was also sinusoidal but shifted according to the deformation. The amplitudes and phase shifts were analyzed for the chains under different conditions .The chains were subjected to the model first as the standalone objects. Then, barrier was defined and chains placed in the vicinity of it. The barrier acted as a volume excluded hindrance. This type of chain molecular dynamics could be used as a stand-alone model or it could be suitable component for complex models, for example network model of polymer nanocomposite.