METHOD OF MAKING AN EXTRUDED MICROCELLULAR POLYMER FOAM PIPE AND DIE

摘要

Described is a pipe of polymer micro-foam material having an impact strength value measured at 0°C which is higher than 100% and up to 400% of the impact strength as required in the EN-norm of a pipe of the same dimensions and basic material in non-foamed condition. Also are described methods for producing such a pipe. Also a die for an extruder is described having, before the slit thereof, a channel which narrows to the slit with an angle alpha between 10 and 180°, preferably 10 and 90°. Further is described an extruder including a die according to the invention.