Ultrasonically assisted polymer extrusion

1 . An extrusion system, comprising:

(a) an ultrasonic component, wherein the ultrasonic component includes:

(i) an ultrasonic transducer having an ultrasonic transducer body; and

(b) an extrusion apparatus configured to receive ultrasonic vibrations from the ultrasonic component, wherein the extrusion apparatus includes:

(i) a rotating single-shaft extruder screw having an upper end and a lower end housed within a barrel,

a) wherein the rotating single-shaft extruder screw is rotated at least 200 revolutions per minute, wherein the barrel is configured to receive material to be extruded therein, and wherein the barrel is heated to a temperature between 50-100° F. above a predetermined flow temperature of the material to be extruded, and

b) wherein the rotating single-shaft extruder screw further includes an internal cavity formed in the lower end thereof that receives a stress-minimizing step stud having a threaded upper portion and a threaded lower portion, wherein the threaded upper portion is greater in diameter than the threaded lower portion, and wherein the stress-minimizing step stud minimizes vibrational stress occurring at the lower end of the rotating single shaft extruder screw;

(ii) a connector coupled with the ultrasonic transducer body and the rotating single-shaft extruder screw,

a) wherein the connector directs ultrasonic energy from the ultrasonic transducer directly into the entire rotating single-shaft extruder screw in a longitudinal manner, and

b) wherein the connector further comprises a collet connected to the ultrasonic transducer body, wherein the collet is configured to receive an upper end of the rotating single-shaft extruder screw; and

(iii) an extrusion die connected to the barrel, wherein the extrusion die is configured to receive and process the material from the barrel; and

(c) wherein the rotating single-shaft extruder screw is tuned to vibrate at the same ultrasonic frequency as the ultrasonic transducer, and wherein the ultrasonic frequency is at least 15 kHz.

2 . The system of claim 1 , wherein the heated barrel further includes an inlet for receiving the material to be extruded, and wherein the inlet includes a source of vibration and a source of cooling air for preventing the material from sticking or melting within the inlet.

3 . The system of claim 1 , wherein the material to be extruded is a polymer, and wherein the polymer is provided in pellet form.