Composite Powders For Laser Sintering

• US 20140264187A1
• Filed: 03/14/2014
• Published: 09/18/2014
• Est. Priority Date: 03/15/2013
• Status: Abandoned Application

• Current Assignee: Carla Lake, Patrick D. Lake
• Original Assignee: Patrick D. Lake
• Inventors: Lake, Carla, Lake, Patrick D.
• Application Number:
  US14/213,324
• Publication Number:
  US 20140264187A1
• Time in Patent Office: Days
• US Class Current: 252/511
• CPC Class Codes: B33Y 70/10 Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials
• CPC Class Codes: C08G 2650/40 containing ketone groups, e.g. polyarylethylketones, PEEK or PEK
• CPC Class Codes: C08K 7/06 Elements
• CPC Class Codes: C08K 7/24 inorganic
• CPC Class Codes: C08L 71/00 Compositions of polyethers obtained by reactions forming an ether link in the main chain of polyacetals C08L59/00; of epoxy resins C08L63/00; of polythioether-ethers C08L81/02; of polyether-sulfones C08L81/06; Compositions of derivatives of such polymers
• CPC Class Codes: H01B 1/24 the conductive material comprising carbon-silicon compounds, carbon or silicon

Abstract

In one aspect, composite powders for laser sintering are described herein. In some embodiments, a composite powder for laser sintering comprises a polymeric matrix and carbon nanofibers disposed in the polymeric matrix. In some embodiments, the polymeric matrix can comprise poly(ether ketone ketone) and the carbon nanofibers can comprise cup-stacked carbon nanotubes.

Claims

1. A composite powder for laser sintering, the powder comprising:

a polymeric matrix; and

carbon nanofibers dispersed in the polymeric matrix, wherein the carbon nanofibers have a bimodal size distribution.

2. The powder of claim 1, wherein the carbon nanofibers comprise a population of long nanofibers and a population of short nanofibers, wherein the average length of the population of long nanofibers is between about 2 times and about 20 times the average length of the population of the short nanofibers.

3. The powder of claim 2, wherein the weight ratio of short nanofibers to long nanofibers is between about 8:

1 and about 1;

8.

4. The powder of claim 1, wherein the polymeric matrix comprises one or more of poly(ether ether ketone) (PEEK), poly(ether ketone ketone) (PEKK), poly(ether ketone) (PEK), poly(arylether ketone) (PAEK), poly(ether ether ketone ketone) (PEEKK), and poly(ether ketone ether ketone ketone) (PEKEKK).

5. The powder of claim 4, wherein the polymeric matrix comprises PEKK.

6. The powder of claim 1, wherein the carbon nanofibers are present in the powder in an amount of up to about 20 weight percent, based on the total weight of the powder.

7. The powder of claim 1, wherein the carbon nanofibers are present in the powder in an amount between about 5 weight percent and about 15 weight percent.

8. The powder of claim 1, wherein the carbon nanofibers comprise cup-stacked carbon nanotubes.

9. The powder of claim 1, wherein the carbon nanofibers comprise single-wall carbon nanotubes or multi-wall carbon nanotubes.

10. The powder of claim 1, wherein the carbon nanofibers have a random orientation within the polymeric matrix.

11. The powder of claim 1, wherein the powder has an average particle size of less than about 100 μ

m.

12. The powder of claim 1, wherein the powder is electrically conductive.

13. A method of forming a 3D article comprising:

providing a layer of granulated particles comprising a composite powder;

exposing at least a portion of the layer of particles to electromagnetic radiation, thereby sintering the particles in the exposed portion, wherein the composite powder comprises a polymeric matrix and carbon nanofibers dispersed in the polymeric matrix, the carbon nanofibers having a bimodal size distribution.

14. The method of claim 13, wherein the polymeric matrix comprises one or more of poly(ether ether ketone) (PEEK), poly(ether ketone ketone) (PEKK), poly(ether ketone) (PEK), poly(arylether ketone) (PAEK), poly(ether ether ketone ketone) (PEEKK), and poly(ether ketone ether ketone ketone) (PEKEKK).

15. The method of claim 14, wherein the carbon nanofibers are present in the powder in an amount of up to about 20 weight percent, based on the total weight of the powder.

16. The method of claim 13, wherein the carbon nanofibers have a random orientation within the polymeric matrix.

17. The method of claim 13, wherein the carbon nanofibers comprise a population of long nanofibers and a population of short nanofibers, wherein the average length of the population of long nanofibers is between about 2 times and about 20 times the average length of the population of the short nanofibers.

18. The method of claim 17, wherein the weight ratio of short nanofibers to long nanofibers is between about 8:

1 and about 1;

8.

19. The method of claim 13, wherein the electromagnetic radiation comprises laser light.

20. The method of claim 13 further comprising providing one or more additional layers of granulated particles comprising the composite powder and exposing at least a portion of each additional layer to electromagnetic radiation to sinter the particles of the exposed portions, wherein the method is carried out in a layer by layer manner to provide the 3D article.