Constitutive modeling of polymers accounting for their hyperelasticity, plasticity, creep and viscoelastic relaxation

The hyperelastic Yeoh model has been generalized to account for creep, plasticity and viscoelasticity of polymers. The general tensorial model developed is applied to several rheometric situations: the tensile test used to measure the stress-strain curve in tension, as well as the creep and recovery tests. The resulting equations are compared to the experimental results acquired in the present work for several monolithic synthetic fibers used as specimens. The comparison revealed that the proposed phenomenological rheological constitutive equation is capable of reproducing the experimental data with a uniformly valid set of physical parameters. Moreover, it was possible to accurately predict the residual plastic deformation of the fibers.