Rheological Properties of High-Viscosity Solutions of Long Molecules

Abstract

IN the kinetic theory of the elasticity of rubber, it is A assumed that on straining at constant volume, the macromoleculpsxlepart from their most probable form with a consequential decrease in their entropy. This applies equally to the coiled or zigzag macromolecules in high-vicosity solutions in which, however, the groups molecules have a much greater freedom of movement relative to one another than in an elastic sotid. The assumption that such movement does taKe place on straining such solutions, in that groups of molecules increase their entropy by moving towards regions of less strain, can be used to explain a number of phenomena experimentally observed in a study of the flow properties of high viscosity solutions.