A Kinetic Network Model for Molten Low-density Polyethylene in Parallel Superposition Vibration Force Field upon Steady Shear Flow

In this paper, the adaptive kinetic network model for describing the rheological properties of structured fluids has been made, which can be used to predict the change of the viscosity and entanglement density for molten low-density polyethylene (LOPE) in parallel superposition vibration force field upon steady shear flow. Recently. our new capillary dynamic rheometer has been developed, which is based on the capillary rheometer with invariable speed, and its equipment s physical model has good agreement with the pulsating extrusion process of round-section die in the condition of electromagnetic dynamic extrusion, and one of the key technologies is that the mechanical vibration force field caused by an electromagnetic field is introduced into the whole plasticating and extrusion process. Through comparing theoretical result with transient experimental data, the theoretical viscosity values and experimental values are reasonably in good agreement, and the changing amplitude of the viscosity increases with the vibration frequency or amplitude increasing, and the effects of vibration frequency or amplitude on the experimental viscosity and the theoretical Viscosity are also accordant. Therefore, the precision of our extended kinetic network model for polymer melt in parallel superposition vibration force field upon steady shear flow is reasonable. Lastly, the change of entanglement density for polymer melt in vibration shear field is studied. As a result, when the vibration frequency or amplitude increases, the entanglement density decrease obviously, while the decreasing amplitude of the 1 entanglement density and the change amplitude of the viscosity increase. INTRODUCTION