Dimensionally stable acrylic alloy for 3-D printing

Patent metadata

Field	Value
Publication number	US-11560473-B2
Application number	US-201716305123-A
Country	US
Kind code	B2
Filing date	May 31, 2017
Priority date	Jun 1, 2016
Publication date	Jan 24, 2023
Grant date	Jan 24, 2023

Abstract

The invention relates to an acrylic alloy composition that can be 3-D printed by a material extrusion additive manufacturing process, to an acrylic filament that has a very uniform diameter useful in the extrusion additive manufacturing process, to acrylic articles made from the acrylic alloy composition by a material extrusion additive process, and to a material extrusion additive manufacturing process for producing the acrylic articles. The acrylic alloy composition is an alloy of an acrylic polymer, and a low melt viscosity polymer, such as polylactic acid. The alloy may optionally be impact modified, preferably with hard core core-shell impact modifiers.

First claim

What is claimed is:

1. An acrylic article made by a material extrusion additive manufacturing process, using an acrylic alloy composition, said acrylic composition comprising:
a polymer matrix blend comprising:
1) one or more acrylic polymers having a weight average molecular weight of from 50,000 to 300,000 g/mol,
2) 5 to 60 weight percent of one or more low viscosity polymers that are compatible, semi-miscible, or miscible with the acrylic polymer, said low viscosity polymers having a melt flow rate of greater than 10 g/10 minutes, as measured by ASTM D1238 at 230° C./10.4 kg of force,
3) optionally 0 to 60 weight percent of impact modifiers,
wherein said acrylic composition has a viscosity at a shear of 1 sec −1 of less than 100,000 Pa-sec at a temperature of 230° C., and a viscosity of 20 to 2,000 Pa-s at a shear rate of 100 sec −1 at a temperature of 230° C., as measured by a rotational viscometer according to ASTM C965.

2. The article of claim 1 , wherein said article has one or more of the following properties:
a) a tensile elongation as measured by ASTM D638 of greater than 10 percent,
b) a fill density of greater than 85 percent,
c) a stress at yield of greater than 35 MPa when measured by ASTM D638,
d) a transmittance of greater than 50% when measured on a 2.1 mm thick sample using ASTM D1003.

3. A filament for 3-D printing comprising an acrylic alloy composition, wherein the filament varies by less than +/−5% in diameter over ten feet of length, said acrylic composition comprising:
a polymer matrix blend comprising:
1) one or more acrylic polymers having a weight average molecular weight of from 50,000 to 300,000 g/mol,
2) 5 to 60 weight percent of one or more low viscosity polymers that are compatible, semi-miscible, or miscible with the acrylic polymer, said low viscosity polymers having a melt flow rate of greater than 10 g/10 minutes, as measured by ASTM D1238 at 230° C./10.4 kg of force,
3) optionally 0 to 60 weight percent of impact modifiers,
wherein said acrylic composition has a viscosity at a shear of 1 sec −1 of less than 100,000 Pa-sec at a temperature of 230° C., and a viscosity of 20 to 2,000 Pa-s at a shear rate of 100 sec −1 at a temperature of 230° C., as measured by a rotational viscometer according to ASTM C965.

4. The filament of claim 3 wherein said filament is a coextruded, multiphase filament.

5. The filament of claim 3 , wherein said multiphase filament comprises a special effect composition that provides visual effects as one of the phases.

6. A process for forming an extrusion additive (3D) acrylic article, comprising the steps of:
presetting the software of a 3D printer to a set volume flow and line spacing for the printing of said article;
feeding an acrylic alloy composition in the form of filament, pellets or powder into the 3D printer;
feeding by the printer of the acrylic composition melt to a heated nozzle;
depositing the acrylic composition melt at the set location, line spacing and flow rate set by the software, to form an article,
said acrylic composition comprising:
a polymer matrix blend comprising:
1) one or more acrylic polymers having a weight average molecular weight of from 50,000 to 300,000 g/mol,
2) 5 to 60 weight percent of one or more low viscosity polymers that are compatible, semi-miscible, or miscible with the acrylic polymer, said low viscosity polymers having a melt flow rate of greater than 10 g/10 minutes, as measured by ASTM D1238 at 230° C./10.4 kg of force,
3) optionally 0 to 60 weight percent of impact modifiers,
wherein said acrylic composition has a viscosity at a shear of 1 sec −1 of less than 100,000 Pa-sec at a temperature of 230° C., and a viscosity of 20 to 2,000 Pa-s at a shear rate of 100 sec −1 at a temperature of 230° C., as measured by a rotational viscometer according to ASTM C965.

7. The process of claim 6 , wherein the flow rate and/or line spacing represents an overflow of from 1-10 percent.

8. The process of claim 6 , wherein said nozzle is heated to between 190° C. and 250° C.

Assignees

• Arkema France
• Liu David Shin Ren
• Reilly Jack J
• Aubart Mark A

Inventors

• Liu David Shin-Ren
• Reilly Jack J
• Aubart Mark A

Classifications

• C08L33/08 Primary

  Homopolymers or copolymers of acrylic acid esters · CPC title

• C08K3/346

  Clay · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title

• B29K2033/08

  Polymers of acrylic acid esters, e.g. PMA, i.e. polymethylacrylate · CPC title

• B33Y70/00

  Materials specially adapted for additive manufacturing · CPC title