METHODS AND APPARATUSES FOR MAKING SUPERFINE FIBERS

• US 20090280325A1
• Filed: 03/16/2009
• Published: 11/12/2009
• Est. Priority Date: 03/17/2008
• Status: Abandoned Application

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Inventors: Lozano, Karen, Sarkar, Kamalaksha
• Application Number:
  US12/404,907
• Publication Number:
  US 20090280325A1
• Time in Patent Office: Days
• US Class Current: 428/401
• CPC Class Codes: D01D 5/06 Wet spinning methods D01D5/0046 takes precedence
• CPC Class Codes: D01D 5/18 by means of rotating spinnerets
• CPC Class Codes: D10B 2201/28 Cellulose esters or ethers, e.g. cellulose acetate
• CPC Class Codes: Y10T 428/298 Physical dimension

Abstract

Apparatuses and methods for the production of superfine fibers.

Claims

1. A method of creating nanofibers, comprising:

heating a material;

placing the material in a heated structure; and

after the placing, rotating the heated structure at a rate of at least 500 revolutions per minute (RPM) to create the nanofibers from the material.

2. The method of claim 1, where the heated structure is rotated at no more than 40,000 RPM.

3. The method of claim 1, where the heated structure is rotated at a rate of 5,000-25,000 RPM.

4. The method of claim 1, where at least 5 milliliters (mL) of the material are positioned in the heated structure, and the heated structure is rotated at a rate of 500-25,000 RPM for at least 10 seconds.

5. The method of claim 1, where the heated structure includes at least one opening and the material is extruded through the opening to create the nanofibers.

6. The method of claim 5, where the heated structure includes multiple openings and the material is extruded through the multiple openings to create the nanofibers.

7. The method of claim 1, where the material is positioned in a reservoir of the heated structure.

8. The method of claim 7, where the reservoir is defined by a concave cavity of the heated structure.

9. The method of claim 8, where the heated structure includes at least one opening in communication with the concave cavity, the nanofiber is extruded through the opening, the heated structure is rotated about a spin axis, and the opening has an opening axis that is not parallel with the spin axis.

10. The method of claim 8, where the heated structure includes multiple openings in communication with the concave cavity.

11. The method of claim 8, where the heated structure includes a body that includes the concave cavity and a lid positioned above the body such that a gap exists between the lid and the body, and the nanofiber is created as a result of the rotated material exiting the concave cavity through the gap.

12. The method of claim 1, where the heated structure is thermally coupled to a heat source that can be used to adjust the temperature of the heated structure before the rotating.

13. The method of claim 1, where the heated structure is heated to a temperature less than 1500°

C.

14. The method of claim 1, where the heated structure comprises a syringe and a plunger.

15. A method of creating a superfine fiber, comprising:

spinning material to create the superfine fiber;

where, as the superfine fiber is being created, the superfine fiber is not subjected to an externally-applied electric field or an externally-applied gas; and

the superfine fiber does not fall into a liquid after being created.

16. A spinneret comprising:

a plate having;

a centrally-oriented reservoir;

a fluid exit pathway in fluid communication with the reservoir; and

a fluid exit opening in fluid communication with the fluid exit pathway; and

a cover coupled to the plate;

where the spinneret is configured such that, during operation, material in the reservoir flows through the fluid exit pathway and out of the spinneret through the fluid exit opening to create a superfine fiber.

17. The spinneret of claim 16, where the plate has:

multiple fluid exit pathways, each in fluid communication with the reservoir; and

one fluid exit opening in fluid communication with each respective fluid exit pathway; and

where the spinneret is configured such that, during operation, material in the reservoir flows through the fluid exit pathways and out of the fluid exit openings to create superfine fibers.

18. The spinneret of claim 17, further comprising:

a holding plate to which both the plate and the cover are coupled in a stacked relationship.

19. An apparatus for creating superfine fibers, comprising:

a driver configured to be rotated at 500 RPM or more;

a spinneret coupled to the driver; and

a superfine fiber collection device;

where the apparatus is configured to create superfine fibers by rotating the spinneret with the driver, and without subjecting the superfine fibers, during their creation, to either an externally-applied electric field or an externally-applied gas, and without the superfine fibers falling into liquid after being created.

20. The apparatus of claim 19, where the driver is configured to be rotated at 5,000-25,000 RPM.

21. The apparatus of claim 19, where the superfine fiber collection device is a collection wall.

22. The apparatus of claim 19, where the superfine fiber collection device is a collection rod.

23. The apparatus of claim 19, where the superfine fiber collection device is an elongated structure with open ends and an open top.

24. The apparatus of claim 19, further comprising:

a heater thermally coupled to the spinneret.

25. The apparatus of claim 19, further comprising:

a cooler thermally coupled to the spinneret.

26. The apparatus of claim 19, further comprising:

an intermediate wall surrounding the superfine fiber collection device.

27. The apparatus of claim 26, further comprising:

a housing surrounding at least the spinneret, the superfine fiber collection device, and the intermediate wall, the housing including an inlet for the introduction of a gas.

28. A nanofiber selected from the group consisting of:

a beta-lactam nanofiber, a polypropylene nanofiber; and

an acrylonitrile butadiene styrene nanofiber.