Abstract: According to the assumptions of the viscoelasticity materials′mechanical models , the 4 elements
model and the Eyring model are selected to imitate the stress relaxation property of the PVC calendered flexible
composites. Based on the relaxation lab test of 3 kinds of samples which are of the same PVC and same textile
material but with different fabric structures , the parameters of the 2 models are calculated and the relaxation
curve is fitted by a method called MatLab. The experimental results show that the PVC calendered flexible
composites follow the non2linear viscoelasticity model and that the structures of the fabrics have little effect on it .