High-temperature soluble support material for additive manufacturing

Patent metadata

Field	Value
Publication number	US-2017087774-A1
Application number	US-201515311719-A
Country	US
Kind code	A1
Filing date	May 13, 2015
Priority date	May 16, 2014
Publication date	Mar 30, 2017
Grant date	—

Abstract

A support material for use in an additive manufacturing system, which includes a thermoplastic copolymer polymerized from monomers comprising acid-functional monomers having carboxylic acid groups, and one or more non-acid-functional monomers, where a portion of the carboxylic acid groups are neutralized with a base having an alkali metal cation. The thermoplastic copolymer has a high glass transition temperature and melt processing temperature, and is thermally stable at its melt processing temperature. The neutralized thermoplastic copolymer is soluble in an alkaline aqueous solution.

First claim

1 . A soluble polymeric material comprising:
a thermoplastic copolymer comprising carboxylic acid groups wherein a portion of the carboxylic acid groups are neutralized to form carboxylic acid salt groups; and wherein the glass transition temperature of the thermoplastic copolymer is greater than about 120° C. and the polymeric material is disintegrable in an alkaline aqueous solution or dispersion.

2 . The material of claim 1 wherein the carboxylic acid salt groups comprise a cation selected from the group consisting of potassium ions, sodium ions and lithium ions.

3 . The material of claim 1 wherein the carboxylic acid groups are neutralized by basic substances selected from the group consisting of potassium bicarbonate, potassium hydroxide, sodium hydroxide and lithium hydroxide.

4 . The material of claim 1 wherein the glass transition temperature of the support material is greater than about 40° C.

5 . The material of claim 1 wherein the melt processing temperature of the thermoplastic copolymer is greater than about 220° C.

6 . The material of claim 1 , wherein the thermoplastic copolymer is polymerized from monomers comprising one or more acid-functional monomers comprising one or more (meth)acrylic acid monomers and from monomers comprising one or more non-acid-functional monomers comprising one or more ethylenically-unsaturated aromatic monomers.

7 . The material of claim 1 , further comprising one or more second acid-functional monomers having carboxyl acid groups and one or more second additional, non-acid monomers functional monomers.

8 . The material of claim 1 , further comprising one or more additives selected from the group consisting of impact modifiers, heat stabilizers, antioxidants, and combinations thereof.

9 . The material of claim 1 wherein the glass transition temperature is greater than about 160° C., and wherein the melt processing temperature is greater than about 250° C.

10 . The material of claim 1 wherein the configuration of the material is either filament or powder.

11 . The material of claim 1 , wherein the material is utilized in an additive manufacturing system, the additive manufacturing system is selected from the group consisting of an extrusion-based additive manufacturing system, a selective laser sintering system, and an electrophotography-based additive manufacturing system.

12 . A method for producing a soluble polymeric material, the method comprising:
providing a thermoplastic copolymer having carboxylic acid group; neutralizing a portion of the carboxylic acid groups of the thermoplastic copolymer with a base comprising alkali metal cations to form carboxylic acid salt groups; and compounding the neutralized thermoplastic copolymer into a media form, wherein the glass transition temperature of the thermoplastic copolymer is greater than about 120° C.

13 . The method of claim 12 , wherein the thermoplastic copolymer is disintegrable in an alkaline aqueous solution.

14 . The method of claim 12 , wherein the base comprising alkali metal cations is selected from the group consisting of potassium bicarbonate, potassium hydroxide, sodium hydroxide and lithium hydroxide.

15 . The method of claim 12 , wherein the neutralization of the carboxyl acid groups is performed by melt processing.

16 . The method of claim 12 , wherein the melt processing temperature of the thermoplastic copolymer with the carboxylic acid salt groups is greater than the melt processing temperature of the thermoplastic copolymer prior to being neutralized.

17 . The method of claim 12 , wherein the thermoplastic copolymer is polymerized from monomers comprising one or more acid-functional monomers comprising one or more (meth)acrylic acid monomers and from monomers comprising one or more non-acid-functional monomers comprising one or more ethylenically-unsaturated aromatic monomers.

18 . A method for printing a three-dimensional part with an additive manufacturing system, the method comprising:
printing the three-dimensional part with a part material and a support structure with a support material wherein the glass transition temperature of the support material is higher than about 120° C., the melt processing temperature is greater than about 220° C. and wherein the support material comprises a thermoplastic copolymer comprising carboxylic acid groups wherein a portion of the carboxylic acid groups are neutralized to form carboxylic acid salt groups.

19 . The method of claim 18 , further comprising disintegrating at least a portion of the support structure in an alkaline aqueous solution.

20 . The method of claim 18 , wherein the carboxylic acid are neutralized by basic substances selected from the group consisting of potassium bicarbonate, potassium hydroxide, sodium hydroxide and lithium hydroxide.

Assignees

• Stratasys Inc

Inventors

• Pawloski Adam R
• Zhu Jiayi
• Kaske Kent
• Rodgers Luke M B
• Sherar Theresa

Classifications

• B29K2105/0085

  Copolymers · CPC title

• C08F2/38

  Polymerisation using regulators, e.g. chain terminating agents {, e.g. telomerisation} · CPC title

• B29C64/40

  Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof · CPC title

• C08F220/06

  Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof · CPC title

• C08F212/08

  Styrene · CPC title