Method for plasticizing particulate plastic material

A method of plasticizing particulate plastic material, comprising the steps of:

• providing a plasticizer, the plasticizer comprising:
• a housing, the housing having a bore therethrough, and the bore having an inlet end and an outlet end;
• an auger positioned in the bore, the auger having a discharge end at an intermediate location in the bore;
• and
• a smooth-walled, cylindrical rotor positioned in the bore between the auger and the outlet end, the bore and the rotor defining an annulus therebetween, and the rotor having a first end positioned proximate to the discharge end of the auger, the rotor having an axial length and the annulus extending from the first end along the length of the rotor;
• feeding the plastic particulate material into the bore at the inlet end;
• rotating the auger at a desired speed and thereby conveying the particulate plastic material at a desired flow rate through the outlet end and frictionally melting the particulate plastic material before passing the discharge end to form a melt;
• and
• rotating the rotor at a desired speed to uniformly heat the melted particulate plastic material passing from the discharge end of the auger and through the annulus to a desired temperature independent of the flow rate of the melted plastic through the annulus.