AMPLITUDE-DEPENDENT DYNAMICAL BEHAVIOR OF PVC

Results of the amplitude-dependent dynamical behavior of commercial po ly(vinyl chloride) are presented. Both the loss factor (internal frict ion) and the storage Young's modulus are strain amplitude dependent wh en measured between room temperature and approximately 400 K at a freq uency of 50 kHz. The data are interpreted in terms of a hyperbolic sin e stress dependence of the strain rate, including an effective stress. The activation volume was found to depend on temperature, with values much larger than those given by the usual mechanical tests (tensile, creep, or stress relaxation). It is suggested that these nonlinear eff ects are related to the cu relaxation. (C) 1996 John Wiley & Sons, Inc .