A Model for Primary Normal Stress Difference of Dynamic Extrusion of a Polymer Melt through a Capillary

Abstract

The dynamic extrusion process of a polymer melt through a capillary under a superimposed vibration has been was researched deeply, and a mathematical model for the primary normal stress difference of a polymer melt under the vibration force field was set up. Accordingly, the calculation steps of above primary normal stress difference were established based on a rheological measuring equipment which was disigned by the authors. The primary normal stress difference of polymer melt under a vibration force field can be calculated by measuring the instantaneous data of capillary die swell, capillary entry pressure, capillary volume flux, and their phase difference under vibration with different frequencies and amplitudes.

Keywords:

• Capillary
• Polymer melt
• Primary normal stress difference
• Vibration

ACKNOWLEDGMENT

The author wishes to acknowledge the financial support provided by the National Nature Science Foundation of China (Project 10672197) and the Scientific Research Fund of Human Provincial Education Department (Project 05C510).