Microlayer and nanolayer tubing and piping via layer multiplication coextrusion. II. Rheologically mismatched systems

An advanced technology, presented in Part 1, was utilized with a custom annular die to produce structures having 9–129 layers. Two material systems were chosen to produce layer structures of viscosity and elasticity stratified type both with/without the application of a rotating boundary wall within the annular land. A maximum rotation window for nine-layer structures was determined to maintain the layer structure while minimizing the appearance of the weld lines and achieving concentric layers. ANSYS Polyflow was utilized in conjunction to study trilayered systems of generic material properties in stratified forms, along with replication of the experimental systems. Combination of experimental and simulation approaches herein are allowing for the achievement of high layer number, low layer thickness, systems in annular form for the first time. The continued development of this technology can lead to application areas of tubes/pipes with advanced properties such as optical filtering, pressure resistance, and permeation reduction. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137, 48684.