a method is disclosed for the manufacture of a powdered polyimide extrudate for use as a purge media . the method includes feeding a polyimide film material into an extruder having a first zone that provides heating and a subsequent second zone that provides endothermic shearing . in one embodiment , the resulting purge media comprises a sheared polyimide powder having an average particle size in a range of about 5 to 100 microns . the purge media can comprises up to 35 weight percent other additives .