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CN-114667211-B - Improved powder for additive manufacturing

CN114667211BCN 114667211 BCN114667211 BCN 114667211BCN-114667211-B

Abstract

The present invention relates to a composition comprising at least one polymer, wherein the polymer is in powder form, and wherein the polymer comprises at least one thermoplastic polymer, wherein the thermoplastic polymer is selected from at least one polyaryletherketone and/or copolymers thereof and/or block copolymers thereof and/or polymer blends thereof, wherein the composition has a Melt Volume Rate (MVR) of at least 5cm 3 /10 min, and a method of manufacture and use thereof. The invention also relates to a method for producing a construction element and to a construction element thereof.

Inventors

  • B. BREWER
  • N. Deke emer
  • D. Fletcher
  • 5. Gritz
  • S. Tuzcoki
  • A. PFISTER

Assignees

  • 阿科玛法国公司
  • EOS有限公司电镀光纤系统

Dates

Publication Date
20260508
Application Date
20201119
Priority Date
20191119

Claims (20)

  1. 1. A composition comprising: At least one of the polymers is selected from the group consisting of, Wherein the polymer is in powder form, and Wherein the polymer comprises at least one thermoplastic polymer, Wherein the thermoplastic polymer is selected from at least one polyaryletherketone and its copolymer and/or its block copolymer and/or its polymer blend, Wherein the composition has a Melt Volume Rate (MVR) of at least 5cm 3 /10 min, and/or not more than 55cm 3 /10 min, Wherein the composition is obtained by a process comprising a step of rounding polymer particles so as to obtain rounded particles by a thermo-mechanical treatment at a temperature of at least 30 ℃ and below the melting point Tm of the polymer, wherein the process optionally comprises a step of grinding the polymer, and The composition is obtained by a process comprising the step of annealing the polymer particles at a temperature of at least 250 ℃ and not more than 285 ℃, Wherein the at least one polyaryletherketone is selected from the group of Polyetherketoneketones (PEKK), Wherein the polyetherketoneketone comprises the following repeating units: Repeating unit A Repeating unit B , Wherein the ratio of the repeating unit a to the repeating unit B is between 70:30 and 40:60.
  2. 2. The composition according to claim 1, Wherein the polymer comprises at least one semi-crystalline polymer, And/or At least one amorphous polymer.
  3. 3. The composition according to claim 1 or 2, Wherein the polyaryletherketone has a melting temperature Tm of at least 250 ℃, and/or at most 320 ℃, and/or wherein the polyaryletherketone has a glass transition temperature Tg of at least 120 ℃, and/or no more than 200 ℃.
  4. 4. The composition according to claim 1, Wherein the Polyetherketoneketone (PEKK) has an extrapolated onset melting temperature T eim of at least 250 ℃, and/or at most 285 ℃.
  5. 5. The composition according to claim 1, The polymer has a process window of at least 1 ℃, and/or no more than 200 ℃.
  6. 6. The composition according to claim 1, Wherein the polymer blend comprises a polyaryletherketone-polyetherimide.
  7. 7. The composition according to claim 1, Wherein the polymer particles of the composition have the following particle size distribution: d10=at least 10 μm and/or not more than 50 μm D50=at least 25 μm and/or not more than 100 μm D90=at least 50 μm and/or not more than 150 μm.
  8. 8. The composition according to claim 1, Wherein the polymer particles of the composition have the following particle size distribution: d10=at least 15 μm and/or not more than 50 μm D50=at least 40 μm and/or not more than 100 μm D90=at least 70 μm and/or not more than 150 μm; Wherein the polymer particles are obtained by grinding a polymer sheet.
  9. 9. The composition according to claim 1, Wherein the composition has a distribution width (d 90-d 10)/d 50 of no more than 3.
  10. 10. The composition according to claim 1 or 2, Wherein the polymer particles have a sphericity of at least 0.8.
  11. 11. The composition according to claim 1, Wherein the composition comprises a primary composition and wherein the content of the primary composition is above 10% and/or below 60% by weight of the total composition.
  12. 12. The composition according to claim 1 or 2, The composition has a pourability of at least 1 second and/or not more than 12 seconds.
  13. 13. The composition according to claim 1, Wherein the composition has a hausner factor of at least 1.01 and/or not more than 1.7.
  14. 14. The composition according to claim 1, Wherein the composition comprises at least one flow agent.
  15. 15. The composition according to claim 14, Wherein the content of the at least one flow agent in the combination is not more than 1% by weight.
  16. 16. The composition according to claim 1, Wherein the composition has a BET specific surface area of at least 0.1m 2 /g and/or not more than 10m 2 /g.
  17. 17. A process for preparing the composition of claim 1, wherein the process comprises the steps of: (i) Providing at least one thermoplastic polymer, wherein the thermoplastic polymer is selected from at least one polyaryletherketone and/or copolymers thereof and/or block copolymers thereof and/or polymer blends thereof, (Ii) The polymer may optionally be ground to a degree, (Iii) Rounding the polymer particles by thermomechanical treatment in a mixer at a temperature of at least 30 ℃ and below the melting point Tm of the polymer, (Iv) The polymer particles are annealed at a temperature of at least 250 ℃ and not more than 285 ℃.
  18. 18. A method for manufacturing a build element, the method comprising the steps of: (i) Applying a layer of the composition according to claim 1 and/or a layer of the composition prepared according to claim 17 onto a production panel, (Ii) Selectively curing a layer of said composition applied at a location representative of the cross section of the object to be manufactured, and (Iii) The carrier is lowered and the applying and curing steps are repeated until the build element is completed.
  19. 19. The method for manufacturing a build element of claim 18, Wherein the step i) of applying the layer is by at least a double coating, Wherein the application of the layers is divided into a step of applying a first layer having a first height H1 and a step of applying a second layer having a second height H2, Wherein a second layer of height H2 is applied over the first layer of height H1.
  20. 20. The composition according to claim 1, Wherein the composition is obtained by the method according to claim 17.

Description

Improved powder for additive manufacturing Technical Field The present application relates to a composition comprising at least one thermoplastic polymer, wherein the composition exhibits a specific melt volume rate to allow for an optimized additive manufacturing process. Furthermore, the application relates to a method for producing the inventive composition and to a device comprising the inventive composition and to the use of the inventive composition. Background Powder build material-based devices and additive manufacturing methods for industrial production of prototypes allow for the manufacture of plastic particles and are becoming increasingly important. By using the manufacturing method, the layers are selectively melted and solidified to produce the desired structure by applying the adhesive and/or the binder, respectively. Methods are also known as "additive manufacturing," digital build, "or" three-dimensional (3D) printing. Industry development methods for making prototypes (prototyping) have been used for decades. However, due to the technological advancement of the system, instead of or in addition to prototypes, the production of components (rapid manufacturing) to meet the quality requirements of the final product is started, i.e. the technological advancement of the current systems also allows the production of components meeting the quality requirements of the final product. In practice, the term "additive manufacturing" is often replaced by the term "regenerative manufacturing" or "rapid technology". Additive manufacturing using powdered materials covers methods that are sintering, melting or bonding by adhesives. Polymer systems are often used as powdered materials for the manufacture of articles. Industrial users of these polymer systems demand good processability, shape accuracy and good mechanical properties of the articles made from these systems. For the purpose of manufacturing such articles, it is advantageous to obtain a bonding of the melted mass to the underlying layers of the 3D structure, since inter-diffusion can only take place in the melted mass. But if the bonding of the layer or layers is insufficient due to insufficient melting properties of the polymer, the 3D article tends to delaminate and lose stability. Therefore, the build temperature during the manufacturing process should be directed to optimize the melt properties of the polymer during the manufacturing process. Thus, in manufacturing 3D articles, the build temperature needs to be above the crystallization temperature of the polymer. On the other hand, in order for the compact not to melt in the build area, the build temperature needs to be substantially lower than the melting temperature. The temperature ranges typically applicable to building objects by additive manufacturing are respectively named process windows or sintering windows of polymers. Disclosure of Invention It is therefore an object of the present invention to predict a composition suitable for use as a material in an additive manufacturing process for producing articles to show process-safe mechanical stability and high shape accuracy. In particular, it is an object of the present invention to provide a composition which exhibits an optimal process window and melting behaviour. According to the invention, such an object is achieved by a composition according to the invention comprising at least one polymer having a defined melt volume rate. Furthermore, the object is achieved by a method according to the invention for preparing the composition, a method according to the invention for manufacturing an object and the use of the composition according to the invention. Accordingly, the present invention relates to a composition, in particular a build material for use in the above additive manufacturing method, comprising: At least one of the polymers is selected from the group consisting of, Wherein the polymer is in powder form, and Wherein the polymer comprises at least one thermoplastic polymer, Wherein the thermoplastic polymer is selected from at least one polyaryletherketone and copolymers and/or block copolymers and/or polymer blends thereof, wherein the composition has at least 5cm 3/10 min, more preferably at least 10cm 3/10 min, and/or no more than 55cm 3/10 min, preferably no more than 40cm 3/10 min, more preferably no more than 30cm 3/10 min, especially preferably no more than 26cm 3/10 min, most preferably no more than 24cm 3/10 min. In its simplest embodiment, the composition of the invention comprises a polymer or polymer system, respectively, selected from thermoplastic polymers. According to the present invention, a "composition" as used herein may include one or more additives. The term "additive" as used herein refers to a substance which may be, inter alia, an amorphous and/or semi-crystalline and/or crystalline polymer, a polyol, a surfactant and/or a protective colloid. The term "powder" as used herein refers to a bulk solid