Fibrous material impregnated with thermoplastic polymer of optimum molecular mass and viscosity and method for the production thereof

Patent metadata

Field	Value
Publication number	US-12173129-B2
Application number	US-201917416098-A
Country	US
Kind code	B2
Filing date	Dec 17, 2019
Priority date	Dec 20, 2018
Publication date	Dec 24, 2024
Grant date	Dec 24, 2024

Abstract

The present invention concerns an impregnated fibrous material comprising at least one continuous-fiber fibrous material in the form of a roving or a plurality of parallel rovings and at least one thermoplastic polymer matrix, characterized in that said at least one thermoplastic polymer is an amorphous or semi-crystalline polymer having a glass transition temperature such that Tg≥40° C., especially Tg≥100° C., in particular ≥120° C., the fiber content of said impregnated fibrous material being from 45 to 65% by volume, preferably from 50 to 60% by volume, especially from 54 to 60% by volume, the number-average molecular mass Mn of said thermoplastic polymer being from 11,000 to 25,000 g/mol, the melt viscosity of said thermoplastic polymer being from 80 to 1500 Pa·s, as measured by plane-plane rheology at 1 Hz and 2% deformation, at a temperature of Tg+220° C.

First claim

The invention claimed is:

1. An impregnated fibrous material comprising at least one continuous-fiber fibrous material in the form of a roving or several parallel rovings and at least one thermoplastic polymer matrix, wherein a thermoplastic polymer of said at least one thermoplastic polymer matrix is an amorphous or semi-crystalline polymer having a glass transition temperature such that Tg≥40° C., as measured using a differential scanning calorimeter (DSC), after a second heating pass, according to standard ISO 11357-2:2013, with a heating and cooling speed of 20° C./min,
the fiber content in said impregnated fibrous material being from 45 to 65% by volume, the number-average molecular mass Mn of said thermoplastic polymer being from 11,000 to 25,000 g/mol, the melt viscosity of said thermoplastic polymer being from 80 to 1500 Pa·s, as measured by plane/plane rheology at 1 Hz and 2% deformation, at a temperature of Tg+220° C.,
wherein the content of fibers by volume is constant in at least 70% of the volume of the impregnated fibrous material.

2. The impregnated fibrous material according to claim 1 , wherein the polymolecularity index Ip of said thermoplastic polymer is from 2 to 6.

3. The impregnated fibrous material according to claim 1 , wherein said at least thermoplastic polymer is chosen from: polyaryl ether ketones (PAEK); polyaryl ether ketone ketone (PAEKK); aromatic polyether imides (PEI); polyaryl sulfones; polyarylsulfides; polyamides (PA); PEBAs; polyolefins, polylactic acid (PLA), polyvinyl alcohol (PVA), and fluorinated polymers; and mixtures thereof.

4. The impregnated fibrous material according to claim 1 , wherein the number-average molecular mass Mn of said thermoplastic polymer is from 14,000 to 25,000, and the molten viscosity of said thermoplastic polymer is from 150 to 1500 Pa·s at a temperature of Tg+220° C., and said thermoplastic polymer is a polymer with Tg≥130° C.

5. The impregnated fibrous material according to claim 4 , wherein said at least thermoplastic polymer is a polyamide.

6. The impregnated fibrous material according to claim 5 , wherein said polyamide is chosen from semi-aromatic polyamides.

7. The fibrous material according to claim 6 , wherein said semi-aromatic polyamide is optionally modified with urea units and chosen from a semi-aromatic polyamide of formula X/YAr, wherein:
Y denotes the residues of an aliphatic diamine having 8 to 20 carbon atoms,
Ar denotes the residues an aromatic dicarboxylic acid group,
X denotes the residues of the NH 2 —(CH 2 ) 10 —COOH aminoundecanoic acid, the lactam 12 or the corresponding amino acid, or the Y,x pattern group from the condensation of the diamine with a dialiphatic acid (x) having between 8 and 20 carbon atoms or to the Y,I pattern group from the condensation of the diamine with isophthalic acid.

8. The impregnated fibrous material according to claim 6 , wherein said semi-aromatic polyamide is chosen from a PA MXDT/6T, a PA MPMDT/6T, a PA 11/BACT, a PA 11/6T/10T, a PA MXDT/10T, a PA MPMDT/10T, a PA BACT/10T, a PA BACT/6T, PA BACT/10T/6T, a PA 11/BACT/6T, a PA 11/MPMDT/6T, PA 11/BACT/10T, a PA 11/MXDT/10T, a PA 11/MXDT/6T.

9. The impregnated fibrous material according to claim 1 , wherein the number-average molecular mass Mn of said thermoplastic polymer is from 11,000 to 20,000 g/mol, the molten viscosity of said thermoplastic polymer is from 80 to 650 Pa·s at a temperature of Tg+220° C., and said thermoplastic polymer is a polyamide with Tg<130° C.

10. The impregnated fibrous material according to claim 9 , wherein said polyamide with Tg<130° C. is chosen from aliphatic polyamides, cycloaliphatic polyamides and semi-aromatic polyamides with Tg less than 130° C.

11. The impregnated fibrous material according to claim 10 , wherein said aliphatic polyamide is chosen among polyamide 6 (PA-6), polyamide 11 (PA-11), polyamide 12 (PA-12), polyamide 66 (PA-66), polyamide 46 (PA-46), polyamide 610 (PA-610), polyamide 612 (PA-612), polyamide 1010 (PA-1010), polyamide 1012 (PA-1012), polyamide 11/1010, polyamide 12/1010, or a mixture thereof or a copolyamide thereof, and block copolymers, and the semi-aromatic polyamides are chosen among MXD10, MXD6, PA 6/6T, a PA 66/6T, a PA 61/6T, MPMDT/10T, 11/MPMDT/10T, MPMDT/6T, a PA BACT/10T, a PA 11/BACT/10T, a MXDT/10 and a PA 11/MXDT/10T.

12. The impregnated fibrous material according to claim 1 , wherein the number of fibers in said fibrous material for carbon fibers is greater than or equal to 3K, or the grammage for the glass fiber is greater than or equal to 1,200 Tex.

13. The impregnated fibrous material according to claim 1 , wherein the fibers of the fibrous material are non-sized.

14. The impregnated fibrous material according to claim 1 , wherein the material has a porosity level, that is the closed porosity level determined by electron microscopy or relative deviation between theoretical density and experimental density, in said impregnated fibrous material of less than 10%.

15. The impregnated fibrous material according to claim 1 , wherein said impregnated fibrous material is single layer.

16. The impregnated fibrous material according to claim 1 , wherein said fibrous material comprises continuous fibers selected from carbon, glass, silicon carbide, basalt, silica, natural fibers or amorphous thermoplastic fibers with a glass transition temperature Tg higher than the Tg of said polymer or said polymer mixture when the latter is amorphous or higher than the Tm of said polymer or said polymer mixture when the latter is semi-crystalline, or the semi-crystalline thermoplastic fibers with a melting temperature Tm higher than the Tg of said polymer or said polymer mixture when the latter is amorphous or higher than the Tm of said polymer or said polymer mixture when the latter is semi-crystalline, or a mixture of two or several of said fibers.

17. The impregnated fibrous material according to claim 1 , wherein said thermoplastic polymer further comprises carbonaceous fillers.

18. The impregnated fibrous material according to claim 1 , wherein said thermoplastic pre-polymer further comprises liquid crystal polymers or cyclic poly(butylene terephthalate), or mixtures containing said liquid crystal polymers or said cyclic poly(butylene terephthalate) as additives.

19. The impregnated fibrous material according to claim 1 , wherein said impregnated fibrous material does not exhibit drapability.

20. A method for preparing an impregnated fibrous material as defined in claim 1 , wherein it comprises a step of pre-impregnating or a step of impregnating said fibrous material with at least thermoplastic polymer being an amorphous or semi-crystalline polymer having a glass transition temperature such that Tg≥40° C., the fiber content in said impregnated fibrous material being from 45 to 65% by volume, the number-average molecular mass Mn of said thermoplastic polymer being from 11,000 to 25,000 g/mol, the melt viscosity of said thermoplastic polymer being from 80 to 1500 Pa·s, as measured by plane/plane rheology at 1 Hz and 2% deformation, at a temperature of Tg+220° C.

21. The method for preparing an impregnated fibrous material according to claim 20 , wherein it comprises a step of impregnating said fibrous material with at least thermoplastic polymer, the number-average molecular mass Mn of said thermoplastic polymer being from 11,000 to 20,000 g/mol, the molten viscosity of said thermoplastic polymer is from 80 to 650 Pa·s at a temperature of Tg+220° C., and said thermoplastic polymer being

Assignees

• Arkema France

Inventors

• Hochstetter Gilles
• Deves Lise
• Capelot Mathieu
• Briffaud Thierry
• Deyrail Yves

Classifications

• C08J2377/10

  Polyamides derived from aromatically bound amino and carboxyl groups of amino carboxylic acids or of polyamines and polycarboxylic acids · CPC title

• C08J2377/00

  Characterised by the use of polyamides obtained by reactions forming a carboxylic amide link in the main chain; Derivatives of such polymers · CPC title

• C08J5/043 Primary

  with glass fibres · CPC title

• C08J5/042 Primary

  with carbon fibres · CPC title