Journal of Theoretical
and Applied Mechanics

51, 1, pp. 117-129, Warsaw 2013

A quasi-linear viscoelastic rheological model for thermoplastics and resins

Cyprian Suchocki
A new rheological model for polymeric materials has been proposed. The model is based on the concept of utilizing the Knowles stored-energy potential within the framework of quasi-linear viscoelasticity theory. The quasi-linear viscoelastic constitutive equation in its general form has been formulated using the formalism of the internal state variables. The developed constitutive equation allows for capturing the nonlinear-viscoelastic behavior of many polymeric materials such as thermoplastics or resins. The model has been implemented into a FE system. An application of the developed constitutive equation to modeling of the short-term, dissipative response of polyethylene has been presented.
Keywords: polymers; rheology; constitutive equation; quasi-linear viscoelasticity; finite element method