Method for the production of tube like foil by extrusion, comprises decelerating and then accelerating flow speed of a coextrudate within an extrusion nozzle

摘要

The method comprises decelerating and then accelerating the flow speed of a coextrudate within an extrusion nozzle. The coextrudate is formed with a flow speed in the extrusion nozzle that is smaller than the discharge speed of the coextrudate from the extrusion nozzle. The foil is coextrudated as a tube foil and discarded during evacuation from a thorn guided through the extrusion nozzle. The pull-off speed of the thorn is higher than the discharge speed of the coextrudate. The foil is formed out of thermoplastically processible polyamide with aromatic structural unit. The method comprises decelerating and then accelerating the flow speed of a coextrudate within an extrusion nozzle. The coextrudate is formed with a flow speed in the extrusion nozzle that is smaller than the discharge speed of the coextrudate from the extrusion nozzle. The foil is coextrudated as a tube foil and discarded during evacuation from a thorn guided through the extrusion nozzle. The pull-off speed of the thorn is higher than the discharge speed of the coextrudate. The foil is formed out of thermoplastically processible polyamide with aromatic structural unit with a wall strength of 0.02-0.4 mm and out of a material based on aliphatic flexibilizing or aliphatic/aromatic polyamide. The barrier layer is formed with a wall strength of 0.01-0.1 mm. An independent claim is included for a device for the production of tube like foil.