Periodic simple shear deformation of polymers in the visco-fluid state

Abstract

Research on the periodic deformation of polymers in the linear and nonlinear regions is reviewed. Special attention is given to the boundary of the region of linear deformation and to deformation in the nonlinear region. It is shown that deformation in the nonlinear region leads to a reversible fall in the viscosity and elasticity of the system due to the selective destruction of certain types of structural bonds. The effect of mineral fillers and the nature of their surfaces on the mechanical characteristics of polymers in the visco-fluid state is stressed. Use of the theory of thixotropy makes it possible to describe the mechanical characteristics of melts in the regions of nonlinear periodic deformation and combined periodic and steady-state deformation on the basis of the results of trivial rheological measurements.