Single-screw extruder for solid state shear extrusion pulverization and method
AssigneeIllinois Institute of Technology
InventorHamid Arastoopour
Life of this patent
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Abstract
A process and apparatus for single screw solid state shear extrusion pulverization of polymeric materials in which the polymeric materials are heated to a temperature suitable for forming a continuous thin film of said polymeric material, and then cooled, and normal and shear forces sufficient to form powder of the polymeric material are applied by a single cylindrical or conical mesh screw. The resulting powder is fluidized upon its discharge.
Claims26
A process for solid state shear extrusion pulverization of a polymeric material comprising:
- heating said polymeric material by heating means, then cooling said polymeric material;
- applying normal and shear forces sufficient to form powder of said polymeric material, said normal and shear forces applied by one of a cylindrical and a conical mesh single screw;
- and
- fluidizing said powder by application of a gas stream.
An apparatus for solid state shear extrusion pulverization of polymeric materials comprising:
- a hollow elongated barrel having a material feed end and a powder discharge end and housing a single screw;
- feed means for feeding a polymeric material to a first zone at said feed end of said hollow elongated barrel;
- discharge means for discharging a pulverized powder from a fourth zone at the discharge end of said hollow elongated barrel;
- heating means for heating said polymeric material to a pre-melt or softening temperature below its melting temperature in a second zone adjacent said first zone;
- cooling means for cooling said polymeric material from said pre-melt or softening temperature to a lower temperature;
- means for applying normal and shear forces sufficient to form fine powder from said polymeric material in a third zone disposed between said second zone and said fourth zone;
- and
- means for fluidizing said powder in a gas stream in at least one of said third zone and said fourth zone, thereby preventing its agglomeration.
Dependencies are inferred from the claim text.