Three-dimensional printed porous silicone matrix using leachable porogen

Patent metadata

Field	Value
Publication number	US-2021269659-A1
Application number	US-202016805494-A
Country	US
Kind code	A1
Filing date	Feb 28, 2020
Priority date	Feb 28, 2020
Publication date	Sep 2, 2021
Grant date	—

Abstract

The silicone-based ink for additive manufacturing includes a siloxane macromer, and a porogen mixture comprising a water-soluble porogen and a surfactant. The product of additive manufacturing with a silicone-based ink includes a three-dimensional printed structure including a plurality of continuous filaments arranged in a predefined pattern and a plurality of inter-filament pores defined by the predefined pattern of the continuous filaments. In addition, each continuous filament of the three-dimensional printed structure includes a silicone matrix having an open cell structure with a plurality of intra-filament pores, and the intra-filament pores form continuous channels through the silicone matrix.

First claim

What is claimed is:

1 . A silicone-based ink for additive manufacturing, the ink comprising:
a siloxane macromer; and a porogen mixture comprising a water-soluble porogen and a surfactant.

2 . The ink as recited in claim 1 , wherein the siloxane macromer includes a vinyl-terminated siloxane macromer.

3 . The ink as recited in claim 1 , wherein the water-soluble porogen includes glycerol.

4 . The ink as recited in claim 3 , wherein a concentration of the glycerol is in a range of about 35 weight % to about 50 weight % of a total weight of the ink.

5 . The ink as recited in claim 1 , wherein the surfactant includes polyvinyl pyrrolidone.

6 . The ink as recited in claim 5 , where in a concentration of the polyvinyl pyrrolidone is in a range of greater than 0 wt % to about 25 weight % of a total weight of the ink.

7 . The ink as recited in claim 1 , further comprising a curing agent.

8 . The ink as recited in claim 1 , comprising an untreated silica.

9 . The ink as recited in claim 1 , comprising a rheology modifying additive.

10 . The ink as recited in claim 1 , wherein the porogen mixture further comprises a plurality of porogen particles.

11 . The ink as recited in claim 10 , wherein the porogen particles are selected from the group consisting of: urea particles, sugar particles, polyethylene glycol, and a combination thereof.

12 . The ink as recited in claim 1 , wherein a concentration of the siloxane macromer is in a range of about 25 weight % to about 70 weight % of a total weight of ink.

13 . A product of additive manufacturing with a silicone-based ink, the product comprising:
a three-dimensional printed structure comprising:
a plurality of continuous filaments arranged in a predefined pattern, the continuous filaments each comprising a silicone matrix having an open cell structure with a plurality of intra-filament pores, wherein the intra-filament pores form continuous channels through the silicone matrix; and
a plurality of inter-filament pores, wherein the inter-filament pores are defined by the predefined pattern of the continuous filaments.

14 . The product as recited in claim 13 , wherein the silicone matrix includes vinyl terminated siloxane polymers.

15 . The product as recited in claim 13 , wherein the continuous filaments have an average diameter greater than about 100 microns.

16 . The product as recited in claim 13 , wherein the inter-filament pores are interconnected from a surface of the three-dimensional printed structure to a surface on an opposite side of the three-dimensional printed structure.

17 . A method of forming a three-dimensional structure comprising a porous silicone matrix, the method comprising:
forming the three-dimensional structure using a siloxane mixture, the siloxane mixture comprising a siloxane macromer and a porogen mixture comprising glycerol and polyvinyl pyrrolidone; curing the formed three-dimensional structure to at least a predefined extent to form a silicone matrix; and leaching the porogen mixture from the silicone matrix to result in a plurality of pores forming interconnected channels through the silicone matrix of the three-dimensional structure.

18 . The method as recited in claim 17 , wherein forming the three-dimensional structure includes extruding a continuous filament of the siloxane mixture through a nozzle to form a printed three-dimensional structure having a plurality of continuous filaments arranged in a predefined pattern.

19 . The method as recited in claim 17 , wherein the forming the three-dimensional structure includes forming a structure selected from the group consisting of: a mold, a cast, and a template.

20 . The method as recited in claim 17 , wherein the siloxane mixture includes a curing agent and a crosslinking agent.

21 . The method as recited in claim 20 , wherein the siloxane mixture includes an effective amount of an inhibitor for controlling a rate of curing by the curing agent.

22 . The method as recited in claim 17 , wherein a concentration of the siloxane macromer is in a range of about 25 weight % to about 70 weight % of a total weight of the siloxane mixture.

23 . The method as recited in claim 17 , wherein a concentration of the glycerol is in a range of about 35 weight % to about 50 weight % of a total weight of the siloxane mixture.

24 . The method as recited in claim 17 , wherein a concentration of the glycerol is in a range of greater than 0 weight % to about 25 weight % of a total weight of the siloxane mixture.

25 . The method as recited in claim 17 , wherein leaching the porogen mixture comprises soaking the three-dimensional structure having the silicone matrix in an aqueous solution to dissolve the porogen mixture.

26 . The method as recited in claim 17 , further comprising, heating the three-dimensional structure having the silicone matrix for setting the silicone matrix.

27 . The method as recited in claim 17 , wherein the porogen mixture further comprises particles selected from the group consisting of: urea particles, sugar particles, polyethylene glycol, and a combination thereof.

28 . The method as recited in claim 17 , wherein the porous silicone matrix has an open cell structure.

Assignees

• L Livermore Nat Security Llc

Inventors

• Nguyen Du
• Duoss Eric
• Lenhardt Jeremy
• Wilson Thomas S

Classifications

• B29C71/00

  After-treatment of articles without altering their shape; Apparatus therefor (B29C44/56, B29C73/00 take precedence; surface shaping B29C59/00 {; for joined or sealed parts B29C66/03; after-treatment specially adapted for vulcanising tyres B29D30/0633}) · CPC title

• B29C2071/0027

  Removing undesirable residual components, e.g. solvents, unreacted monomers · CPC title

• C09D11/106

  containing macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• C09D11/102 Primary

  containing macromolecular compounds obtained by reactions other than those only involving unsaturated carbon-to-carbon bonds · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title