An apparatus for solid state shear extrusion pulverization of a polymeric material comprising an elongated hollow barrel having a feed zone, a heating zone adjacent to the feed zone, a powder... Show moreAn apparatus for solid state shear extrusion pulverization of a polymeric material comprising an elongated hollow barrel having a feed zone, a heating zone adjacent to the feed zone, a powder formation zone adjacent to the heating zone, and a powder discharge zone adjacent to the powder formation zone. At least one screw is housed within the elongated hollow barrel. A hopper is provided for feeding the polymeric material into the feed zone of the elongated hollow barrel. Barrel heaters and coolers are provided for heating the polymeric material to a temperature less than its decomposition temperature in the heating zone and for maintaining the polymeric material below its melting point in the powder formation zone. The screw comprises a high shear screw section for applying normal and shear forces within the powder formation zone to form a powder of the solid state polymeric material. Show less