Method for impregnating reinforcing fibres with polyaryletherketones and semi-products obtained therefrom

Patent metadata

Field	Value
Publication number	US-12384894-B2
Application number	US-202318321904-A
Country	US
Kind code	B2
Filing date	May 23, 2023
Priority date	Apr 5, 2017
Publication date	Aug 12, 2025
Grant date	Aug 12, 2025

Abstract

A process for the preparation of a semifinished product including a PAEK-based resin and reinforcing fibers, including the stages of: a. preparation of a dispersion including a PAEK-based resin in the pulverulent form dispersed in an aqueous phase including a surfactant; b. bringing the reinforcing fibers into contact with said aqueous dispersion; c. drying the fibers impregnated with dispersion; and d. heating the impregnated fibers to a temperature sufficient for the melting of the resin, so as to form a semifinished product, wherein the surfactant is a thermally stable surfactant. Also, semifinished products capable of being obtained from the process and their use in the manufacture of composite materials.

First claim

The invention claimed is:

1. A process for the preparation of a semifinished product comprising a poly(aryl ether ketone) (PAEK)-based resin and reinforcing fibers, comprising the stages of:
a. preparation of a dispersion comprising the PAEK-based resin in pulverulent form dispersed in an aqueous phase comprising at least one surfactant and, if an additive is present, only additives selected from the group consisting of antifoaming agents and biocidal agents;
b. bringing the reinforcing fibers into contact with said aqueous dispersion;
c. drying the fibers impregnated with dispersion; and
d. heating the impregnated fibers to a temperature sufficient for the melting of the resin, so as to form a semifinished product,
wherein the surfactant is a thermally stable surfactant which does not increase the weight-average molecular weight of the PAEK-based resin, as measured by size exclusion chromatographic analysis, by more than 20% after the heating stage.

2. The preparation process as claimed in claim 1 , in which the surfactant comprises aromatic groups.

3. The preparation process as claimed in claim 1 , in which the surfactant comprises a phosphoric acid, phosphate or sulfonate group.

4. The preparation process as claimed in claim 1 , in which the reinforcing fibers are carbon fibers.

5. The preparation process as claimed in claim 1 , in which the reinforcing fibers are nonsized fibers.

6. The preparation process as claimed in claim 1 , in which the reinforcing fibers are fibers sized with a thermally stable size.

7. The preparation process as claimed in claim 1 , in which the PAEK resin is chosen from the group consisting of poly(ether ketone) (PEK), poly(ether ether ketone) (PEEK), poly(ether ether ketone ketone) (PEEKK), poly(ether ether ketone ketone) (PEKK), poly(ether ketone ether ketone ketone) (PEKEKK), poly(ether ether ketone ether ketone) (PEEKEK), poly(ether ether ether ketone) (PEEEK) and poly(ether diphenyl ether ketone) (PEDEK), their mixtures and their copolymers with one another or with other members of the family of the PAEKs.

8. The preparation process as claimed in claim 1 , in which the PAEK resin is a PEKK exhibiting a percentage by weight of terephthalic units, with respect to the sum of the terephthalic and isophthalic units, of between 35% and 100%.

9. The preparation process as claimed in claim 1 , in which the pulverulent PAEK resin in the dispersion exhibits a volume median diameter Dv50, as measured according to the standard ISO 13 320, of 1 to 300 μm.

10. The preparation process as claimed in claim 1 , in which the semifinished product is chosen from a prepreg or a tape.

11. The preparation process as claimed in claim 1 , in which the dispersion comprises:
a. 1% to 50% by weight of the PAEK-based resin, the PAEK-based resin exhibiting a Dv50 diameter, as measured according to the standard ISO 13 320, of between 1 and 300 μm;
b. 0.001% to 5% by weight, calculated with respect to the weight of the PAEK-based resin, of the at least one thermally stable surfactant;
c. 0%-1% by weight of the additives; and
d. the remainder water.

12. The preparation process as claimed in claim 1 , wherein the dispersion possesses a viscosity of less than 10 Pa·s at 20° C., and the viscosity of the dispersion at 375° C. does not increase by more than 20% throughout the preparation process.

13. The preparation process as claimed in claim 1 , wherein the PAEK-based resin exhibits a change in viscosity at 375° C. of less than 20% throughout the preparation process.

14. The preparation process as claimed in claim 1 , in which the surfactant comprises a phosphoric, phosphate or sulfonate group and comprises aromatic groups; or in which the surfactant is chosen from phosphoric acid esters, alkyl ether phosphoric acids, alkyl ether phosphates, alkyl ether sulfonates, alkylaryl ether phosphates, or alkylaryl ether sulfonates.

15. The preparation process as claimed in claim 1 , in which the surfactant comprises a phosphoric, phosphate or sulfonate group and comprises aromatic groups.

16. The preparation process as claimed in claim 1 , in which the surfactant is chosen from phosphoric acid esters, alkyl ether phosphoric acids, alkyl ether phosphates, alkyl ether sulfonates, alkylaryl ether phosphates, or alkylaryl ether sulfonates.

Assignees

• Arkema France

Inventors

• Brule Benoît
• Cayzac Henri-Alexandre
• Le Guillaume
• Pascal Jerome
• Sguerra Fabien

Classifications

• C08J2361/18

  Condensation polymers of aldehydes or ketones with aromatic hydrocarbons or their halogen derivatives only · CPC title

• C08J2329/12

  Homopolymers or copolymers of unsaturated ketones · CPC title

• C08J2329/10

  Homopolymers or copolymers of unsaturated ethers (C08J2335/08 takes precedence) · CPC title

• C08J2300/22

  Thermoplastic resins · CPC title

• C08J5/249 Primary

  characterised by the additives used in the prepolymer mixture · CPC title