Simulations of excluded volume effects due to chain thickness and solvent quality on the chain vector distributions and mean coil dimensions

Abstract

AbstractLattice simulations of chains in good, theta and poor solvents were performed with an explicit incorporation of the excluded volume (chain thickness) into the model. The scaling power law for chain dimensions was found to apply in the theta and athermal states and to fail in the region below the theta state where collapsed chains with voids inside a globule occur. The solvent‐induced globule‐to‐coil transition is transparently manifested by changes in the chain vector distribution functions. In the region of small and medium chain elongations, the simulation data can be fitted in the theta solvent by a Gaussian distribution function and in the athermal solvent by a function due to Oono et al. The stored elastic energy of the chains with fixed ends was calculated as a function of the chain‐end displacement for fully flexible molecules in all three types of solvent and for poly(methylene).