Filament compositions for fused filament fabrication and methods of use thereof

Patent metadata

Field	Value
Publication number	US-11760872-B2
Application number	US-201716340742-A
Country	US
Kind code	B2
Filing date	Oct 12, 2017
Priority date	Oct 21, 2016
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

The disclosure generally relates to filaments and in particular, filaments for use in fused filament fabrication to prepare 3D printed articles. The filaments comprising a polymer composition, said polymer composition comprising: a) about 5 wt. % to about 60 wt. % of a thermoplastic polymer A having a melting peak temperature greater than 40° C.; b) about 95 wt. % to about 40 wt. % of a thermoplastic polymer B having a melting peak temperature greater than 20° C.; c) optionally from about 0.1 to 3 wt. % of a viscosity modifier; wherein: the melting peak temperature of thermoplastic polymer A is at least 20° C. greater than the melting peak temperature of thermoplastic polymer B; thermoplastic polymer A is dispersed in thermoplastic polymer B; and the polymer composition has a melt index of at least 0.1 g/10 minutes using a 10 kg weight measured according to ASTM D1238-13 at a temperature which is less than the melting peak temperature of thermoplastic polymer A and which is greater than the melting peak temperature of thermoplastic polymer B.

First claim

The invention claimed is:

1. A filament for use in fused filament fabrication, said filament comprising a polymer composition, said polymer composition comprising:
a) about 5 wt. % to about 60 wt. % of a thermoplastic polymer A having a melting peak temperature greater than 40° C.;
b) about 95 wt. % to about 40 wt. % of a thermoplastic polymer B having a melting peak temperature greater than 20° C.;
c) optionally from about 0.1 to 3 wt. % of a viscosity modifier;
wherein:
thermoplastic polymer A is a polyamide and thermoplastic polymer B is selected from the group consisting of polyamide-ethers and polyamide-ester copolymers;
the melting peak temperature of thermoplastic polymer A is at least 20° C. greater than the melting peak temperature of thermoplastic polymer B;
thermoplastic polymer A is dispersed in thermoplastic polymer B; and
the polymer composition has a melt index of at least 0.1 g/10 minutes using a 10 kg weight measured according to ASTM D1238-13 at a temperature which is less than the melting peak temperature of thermoplastic polymer A and which is greater than the melting peak temperature of thermoplastic polymer B.

2. An article prepared from the filament of claim 1 using a fused filament fabrication process.

3. The filament of claim 1 in which viscosity modifier (c) is present.

4. The filament of claim 1 wherein the polymer composition exhibits a melt index of at least 0.1 g/10 minutes at a temperature which is at least 10° C. less than the melting peak temperature of thermoplastic A and at least 10° C. greater than the melting peak temperature of thermoplastic B.

5. A process for making the filament of claim 1 comprising:
1) mixing thermoplastic polymer A and thermoplastic polymer B, and optionally viscosity modifiers or additional additives, at a temperature greater than the melting peak temperature of thermoplastic polymer A to form a melt mixture;
2) extruding the melt mixture through a die and cooling the mixture to form a filament.

6. A process for making the filament of claim 1 comprising:
1) pellets of the polymer composition are fed into an extruder in which the temperature in the extruder is greater than the melting peak temperature of thermoplastic polymer B;
2) extruding the melt mixture through a die and cooling the mixture to form a filament.

7. A process for making an article by fused filament fabrication comprising:
1) feeding a filament comprising the polymer composition of claim 1 through a heated die at a temperature less than the melting peak temperature of thermoplastic polymer A but greater than the peak melting temperature of thermoplastic polymer B to form a polymer melt;
2) depositing the polymer melt in a layer-by-layer fashion to form the desired article.

Assignees

• Du Pont
• Dupont Polymers Inc

Inventors

• Fox Peter Anthony
• Oriani Steven R

Classifications

• C08L23/0876 Primary

  Salts thereof, i.e. ionomers · CPC title

• C08L67/00 Primary

  Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain (of polyester-amides C08L77/12; of polyester-imides C08L79/08); Compositions of derivatives of such polymers · CPC title

• C08L23/04

  Homopolymers or copolymers of ethene · CPC title

• C08L23/0853

  Ethylene vinyl acetate copolymers · CPC title

• C08L23/0869

  with unsaturated acids, e.g. [meth]acrylic acid; with unsaturated esters, e.g. [meth]acrylic acid esters · CPC title