Properties of a single chain embedded into a polymer matrix of varied thermodynamic quality and density

Abstract

AbstractThe properties (squared dimensions, anisotropy, numbers of intra‐ and intermolecular contacts) of a single five‐way cubic lattice chain embedded into an environment (matrix) of chains of the same length n = 50 were evaluated as a function of matrix volume fraction (matrix density) v and intermolecular interaction between the matrix polymer and the minority chain segments, characterized by a parameter ϕ. No convincing evidence was found for the occurrence of a coil‐globule transition in the range of matrix densities (v ≤ 0.7) and repulsive interactions between matrix and minority chain (ϕ ≤ 0.2) investigated. For moderate attractive interaction (ϕ ≈ −0.17) a compensation of the chaincompressing action of the matrix and the chain‐expanding interaction with the matrix was observed resulting in a zero‐dependence of the size and shape of the minority chain on matrix density. It further turned out that there are fixed relations among the various size and shape data irrespective of the specific combination of matrix density and thermodynamic interaction by which a particular polymer dimension is produced. These interrelations are fairly the same as those evaluated for isolated chains the size of which is varied by an intramolecular energy parameter ϕi.