Effect of Coextrusion on Bubble Kinematics, Temperature Distribution and Property Development in the Blown Film Process, 1998 Polymers, Laminations & Coatings Conference Proceedings
The bubble shape, velocity profile and strain history in the region between the die exit and frost line in the blown film process is known to influence film properties. The kinematics in coextrusion is dictated by the material that freezes first. The maximum rate of strain of the remaining layers may occur at a higher temperature, affecting film properties. An example of a HDPE resin extruded alone and coextruded with EVOH is considered.