Semicrystalline polyphenylsulfone and associated method of making and method of additive manufacturing

Patent metadata

Field	Value
Publication number	US-11512169-B2
Application number	US-201916973893-A
Country	US
Kind code	B2
Filing date	Jun 26, 2019
Priority date	Jun 27, 2018
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

A semicrystalline polyphenylsulfone, has the structure Formula (I) wherein n and R are defined herein. The semicrystalline polyphenylsulfone, which exhibits a crystalline melting point in a range of 215 to 270° C., can be prepared from amorphous polyphenylsulfone using a solvent-induced crystallization method. An additive manufacturing method utilizing particles of the semicrystalline polyphenylsulfone is described.

First claim

The invention claimed is:

1. A semicrystalline polyphenylsulfone,
wherein the semicrystalline polyphenylsulfone has the structure

wherein n is, on average, 30 to 200, and each occurrence of R is independently C 1 -C 18 alkyl or C 6 -C 18 aryl; and
wherein the semicrystalline polyphenylsulfone exhibits a crystalline melting point in a range of 215 to 270° C., determined according to ASTM D3418-15 by differential scanning calorimetry using a heating rate of 20° C./minute, wherein the semicrystalline polyphenylsulfone is produced by a method comprising: combining a solvent mixture with an amorphous polyphenylsulfone powder in a weight ratio of 1:1 to 100:1, respectively, to form a mixture; wherein the solvent mixture comprises a solvent for the polyphenylsulfone and a non-solvent for the polyphenylsulfone in a weight ratio of 0.5:1 to 10:1, respectively; agitating the mixture for a time of 5 to 500 minutes and at a temperature of 10 to 50° C. to form a dispersion of semicrystalline polyphenylsulfone particles; and isolating the semicrystalline polyphenylsulfone particles from the dispersion.

2. The semicrystalline polyphenylsulfone of claim 1 , wherein a molten polyphenylsulfone obtained on melting the semicrystalline polyphenylsulfone exhibits a zero-shear viscosity in a range of 10 to 10 4 Pascal-second determined according to ASTM D4440-15 at a temperature of 380° C.

3. Particles comprising the semicrystalline polyphenylsulfone of claim 1 , wherein the particles have a volume-based equivalent spherical diameter (Dv50) of 10 to 400 micrometers, determined by laser diffraction according to ISO 13320-1, or the particles have a Dv50 value of 45 to 80 micrometers and a Dv10 value of 1 to 45 micrometers and a Dv90 value of 80 to 125 micrometers determined by laser diffraction according to ISO 13320-1.

4. The semicrystalline polyphenylsulfone of claim 1 , exhibiting two crystalline melting points in the range of 215 to 270° C.

5. The semicrystalline polyphenylsulfone of claim 1 , wherein each occurrence of R is methyl;
a molten polyphenylsulfone obtained on melting the semicrystalline polyphenylsulfone exhibits a zero-shear viscosity of 10 to 10 4 Pascal-second determined according to ASTM D4440-15 at a temperature of 380° C.;
the semicrystalline polyphenylsulfone is in the form of particles having a volume-based equivalent spherical diameter of 10 to 400 micrometers, determined by laser diffraction according to ISO 13320-1; and
the semicrystalline polyphenylsulfone has a hydroxyl end group content greater than 0 and less than 50 parts per million by weight, based on the weight of the semicrystalline polyphenylsulfone.

6. A method of forming a semicrystalline polyphenylsulfone, the method comprising:
combining a solvent mixture with an amorphous polyphenylsulfone powder in a weight ratio of 1:1 to 100:1, respectively, to form a mixture; wherein the solvent mixture comprises a solvent for the polyphenylsulfone and a non-solvent for the polyphenylsulfone in a weight ratio of 0.5:1 to 10:1, respectively;
agitating the mixture for a time of 5 to 500 minutes and at a temperature of 10 to 50° C. to form a dispersion of semicrystalline polyphenylsulfone particles; and
isolating the semicrystalline polyphenylsulfone particles from the dispersion.

7. The method of claim 6 , wherein the amorphous polyphenylsulfone powder has a volume-based equivalent spherical diameter of 10 to 400 micrometers, determined by laser diffraction according to ISO 13320-1.

8. The method of claim 6 , wherein the isolated semicrystalline polyphenylsulfone particles have a volume-based equivalent spherical diameter of 10 to 400 micrometers, determined by laser diffraction according to ISO 13320-1.

9. The method of claim 6 , wherein
the solvent for the polyphenylsulfone is characterized by a polarity of 4 to 8, and a boiling point at atmospheric pressure of 60 to 190° C.; and
the non-solvent for the polyphenylsulfone is selected from the group consisting of C 1 -C 6 alcohols, C 3 -C 6 ketones, and combinations thereof.

10. The method of claim 6 , wherein the solvent for the polyphenylsulfone is selected from the group consisting of dimethylacetamide, dimethylformamide, tetrahydrofuran, pyridine, N-methyl-2-pyrrolidone, and combinations thereof.

11. The method of claim 6 , wherein the non-solvent for the polyphenylsulfone is selected from the group consisting of C 1 -C 6 alcohols and combinations thereof.

12. The method of claim 6 ,
wherein the amorphous polyphenylsulfone powder has a volume-based equivalent spherical diameter of 10 to 400 micrometers, determined by laser diffraction according to ISO 13320-1;
wherein the solvent mixture and the amorphous polyphenylsulfone powder are combined in a weight ratio of 2:1 to 40:1;
wherein the solvent mixture comprises the solvent for the polyphenylsulfone and the non-solvent for the polyphenylsulfone in a weight ratio of 0.7:1 to 3:1, respectively;
wherein the solvent for the polyphenylsulfone is selected from the group consisting of dimethylacetamide, dimethylformamide, tetrahydrofuran, pyridine, N-methyl-2-pyrrolidone, and combinations thereof;
wherein the non-solvent for the polyphenylsulfone comprises methanol; and
wherein the isolated semicrystalline polyphenylsulfone particles have a volume-based equivalent spherical diameter of 10 to 400 micrometers, determined by laser diffraction according to ISO 13320-1.

13. A method of additive manufacturing, the method comprising:
depositing a first layer comprising the semicrystalline polyphenylsulfone particles of claim 3 at a working area;
irradiating the working area with first radiation effective to heat the first layer to a temperature below and within 10° C. of a crystalline melting onset temperature of the semicrystalline polyphenylsulfone particles; and
selectively irradiating a portion of the working area with second radiation effective to heat the first layer to a temperature above a crystalline melting point of the semicrystalline polyphenylsulfone particles.

14. The method of claim 13 , wherein the second radiation comprises laser radiation at a wavelength of 10.6 micrometers.

15. The method of claim 13 , wherein
each occurrence of R is methyl; and
the irradiating the working area with second radiation produces molten polyphenylsulfone exhibiting a zero-shear viscosity of 10 to 10 4 Pascal-second determined according to ASTM D4440-15 at a temperature of 380° C.

Assignees

• Shpp Global Tech Bv

Inventors

• Miloskovska Elena
• Jofore Bruke
• Gallucci Robert Russell

Classifications

• C08L81/06

  Polysulfones; Polyethersulfones · CPC title

• C08G65/40

  from phenols (I) and other compounds (II), e.g. OH-Ar-OH + X-Ar-X, where X is halogen atom, i.e. leaving group · CPC title

• C08G75/00

  Macromolecular compounds obtained by reactions forming a linkage containing sulfur with or without nitrogen, oxygen, or carbon in the main chain of the macromolecule · CPC title

• B29K2081/06

  PSU, i.e. polysulfones; PES, i.e. polyethersulfones or derivatives thereof · CPC title

• C08G75/23 Primary

  Polyethersulfones · CPC title