The objective is to develop theoretical flow-induced orientation stress-strain relationship models for entangled polymer melt during injection molding process with the isothermal compressible hypothesis. In view of the trackless deformation characteristics of polymer entanglement macromolecular chain, the end-to-end distance vector(ETEV) is used to describe the evolution of the macromolecular chain morphology during the filling stage based on some reasonable simplified hypothesis, as the core of the flow-in...