Improved interfacial surface generator for the co-extrusion of micro- and nanolayered polymers

Abstract

Two dies for polymer co-extrusion layer multiplication are evaluated experimentally and computationally in terms of pressure drop and layer uniformity. The first design is that of the original die, is compact, and has successfully been used to co-extrude low elasticity polymers with closely matched rheological properties. The second die design, the one that is being modified, achieves a more balanced flow path with constant cross-sectional area. Flow visualization experiments and computational simulations show matched performance between the dies when layering similar viscosity materials and better layering performance of rheologically dissimilar materials with the improved dies compared to the original die design. Furthermore, the improved die has a much lower pressure drop. This facilitates decreased energy consumption or the allowance of additional multiplier dies to be added resulting in an increased total number of layers. POLYM. ENG. SCI., 54:636–645, 2014. © 2013 Society of Plastics Engineers