On some rheological phenomena of amorphous polymers

The molecular domain model for flexible macromolecules is presented in brief, and various observations are enumerated, indicating that the model holds true for the solid, melt, and solutions of different concentrations. The four forms in which the domains can exist under shear stress are then presented, and, by referring to them, such rheological phenomena as “die swell,” sudden jumps in flow rate, critical concentrations, and changes in viscosity are qualitatively explained.