NONLINEAR CONSTITUTIVE-EQUATIONS FOR VISCOELASTIC BEHAVIOR OF ELASTOMERS AT LARGE DEFORMATIONS

A non-linear theory of viscoelasticity for large deformation of elasto mers has been developed. The concept of an internal variable stress wh ich is governed by a rate equation, has been used to account for the v iscoelastic behaviour of incompressible rubbers. Following a molecular approach the parameters of the model were extracted by the inverse La ngevin approximation of rubber elasticity. Qualitative applications we re made in the case of uniaxial elongation and simple shear deformatio ns. (C) Elsevier Science Limited.