Molecular dynamics of chain molecules in solution. Static and dynamic properties

Abstract

Molecular dynamics simulations have been performed for systems of chains composed of Nc =8–20 units immersed in 343-Nc solvent molecules. Two different types of forces (rigid and elastic) between neighboring chain units are considered. Also, different values of the interaction between chain units and solvent molecules are introduced. Distribution functions of distances, dimensions, time-correlation functions and translational diffusion coefficients are calculated from the simulation results. The values of these properties show that the elastic model corresponds to a more expanded chain. More expanded chains are also simulated with more favorable polymer–solvent interactions. Slower relaxation times are obtained for the expanded chains. Scaling laws for dimensions and diffusion coefficients in terms of the chain lengths are investigated.