High strength polyvinylidene fluoride based sized reinforcing fibers

Patent metadata

Field	Value
Publication number	US-11840800-B2
Application number	US-201816630610-A
Country	US
Kind code	B2
Filing date	Jul 16, 2018
Priority date	Jul 14, 2017
Publication date	Dec 12, 2023
Grant date	Dec 12, 2023

Abstract

The invention relates to sized reinforcing fibers that comprise a reinforcing fiber sized with a fluoropolymer. The fluoropolymer is functionalized and/or the reinforcing fiber is sized with a compatible functional non-fluorinated polymer that is compatible with the fluoropolymer. Functionalization of the fluoropolymer or the compatible non-fluorinated polymer provides enhanced properties, such as increased adhesion to the reinforcing fiber.

First claim

What is claimed is:

1. A sized reinforcing fiber comprising:
a) a reinforcing fiber selected from the group consisting of carbon fiber, aramid fiber, and glass fiber; and
b) at least one sizing comprising functionalized polymer said polymer selected from the group consisting of:
i) both a functionalized vinylidene fluoride polymer (PVDF polymer), and a compatible functional non-fluorinated polymer, wherein the functionalized PVDF polymer is a copolymer comprising copolymerized fluoromonomer and functional comonomer or is a functionalized block PVDF polymer having a PVDF polymer block and a low molecular weight functional polymer block, wherein at least one functional group of the compatible functional non-fluorinated polymer is bonded to the reinforcing fiber, and
ii) a functionalized PVDF copolymer and a compatible functional non-fluorinated polymer, comprising VDF monomer, copolymerized with optional fluorinated comonomer, and at least one functional comonomer, wherein at least one functional group of the PVDF copolymer is adhered to the reinforcing fiber,

wherein the functionalized PVDF is not grafted with maleic anhydride, wherein the functionalized PVDF is fluorosurfactant free and wherein the fluoromonomers in the PVDF are vinylidene fluoride (VDF), and the optional fluorinated comonomer is selected from the group consisting of, tetrafluoroethylene (TFE), trifluoroethylene (TrFE), chlorotrifluoroethylene (CTFE), hexafluoropropene (HFP), 2,3,3,3-tetrafluoropropene, 3,3,3-trifluoropropene, vinyl fluoride (VF), pentafluoropropene, perfluoromethyl vinyl ether (PMVE), perfluoropropylvinyl ether, hydrophilic monomers containing a fluorine atom and combinations thereof,
wherein at least one functional group of the compatible functional non-fluorinated polymer is bonded to the reinforcing fiber and wherein the compatible functional non-fluorinated polymer is a functional acrylic copolymer including at least one methacrylic acid monomer and at least one methyl methacrylate monomer.

2. The sized reinforcing fiber of claim 1 , wherein the sizing includes a functionalized block PVDF having a PVDF block and a low molecular weight functional polymer block.

3. The sized reinforcing fiber of claim 2 , wherein the low molecular weight functional polymer results from a chain transfer agent selected from the group consisting of polyacrylic acid, polylactic acid, polyphosphonic acid, polysulfonic acid, and polymaleic acid; and partially or fully neutralized and/or esterified forms of said acids; and combination thereof.

4. The sized reinforcing fiber of claim 1 , wherein said functionalized PVDF comprises a copolymerized functional hydrophilic monomer.

5. The sized reinforcing fiber of claim 1 , wherein said sizing comprises a block copolymer having a PVDF block and a functional non-fluoropolymer block.

6. The sized reinforcing fiber of claim 1 , wherein the reinforcing fiber is aramid fiber.

7. The sized reinforcing fiber of claim 1 , wherein the reinforcing fiber is glass fiber.

8. The sized reinforcing fiber of claim 1 , further comprising the compatible functional non-fluorinated polymer, wherein the compatible functional non-fluorinated polymer includes at least one monomer selected from the group consisting of α,β unsaturated carboxylic acids, an acrylic monomer containing a hydroxyl group, a monomer containing an epoxy group, a monomer containing silanols, a monomer containing an aldehyde, an alkenyl cyanide, and acetoacetoxyethyl methacrylate.

9. The sized reinforcing fiber of claim 1 , further comprising the compatible functional non-fluorinated polymer, wherein the compatible functional non-fluorinated polymer includes at least one monomer selected from the group consisting of acrylic acid, methacrylic acid, fumaric acid, crotonic acid, itaconic acid, hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, diethylene glycol ethyl ether acrylate, glycidyl acrylate, glycidyl methacrylate, γ-trimethoxysilane methacrylate, γ-triethoxysilane methacrylate, acrolein, acrylonitrile, methacrylonitrile, and acetoacetoxyethyl methacrylate.

10. The sized reinforcing fiber of claim 1 , wherein the reinforcing fiber is carbon fiber.

11. A sized reinforcing fiber comprising:
a) a reinforcing fiber selected from the group consisting of carbon fiber and aramid fiber;
b) a first sizing polymer containing at least one functional group; and
c) at least one further sizing comprising functionalized polymer said polymer selected from the group consisting of:
i) a functionalized vinylidene fluoride polymer (PVDF), containing a low molecular weight functional polymer chain transfer agent, and wherein at least one functional group of the functionalized PVDF is bonded to the first sizing polymer;
ii) both a functionalized PVDF polymer and a compatible functional non-fluorinated polymer, wherein at least one functional group of the compatible functional non-fluorinated polymer is bonded to the first sizing polymer; and
iii) a functionalized PVDF copolymer comprising VDF monomer, optional fluorinated comonomer, and at least one functional comonomer, wherein at least one functional group of the PVDF copolymer is adhered to the first sizing polymer,

wherein the functionalized PVDF is not grafted with maleic anhydride, and wherein the fluoromonomers in the PVDF are selected from the group consisting of vinylidene fluoride (VDF), tetrafluoroethylene (TFE), trifluoroethylene (TrFE), chlorotrifluoroethylene (CTFE), hexafluoropropene (HFP), 2,3,3,3-tetrafluoropropene, 3,3,3-trifluoropropene, vinyl fluoride (VF), pentafluoropropene, perfluoromethyl vinyl ether (PMVE), perfluoropropylvinyl ether and hydrophilic monomers containing a fluorine atom.

12. The sized reinforcing fiber of claim 11 , wherein the reinforcing fiber is carbon fiber and the first polymer is compatible with the carbon fiber.

13. The sized reinforcing fiber of claim 11 , wherein the low molecular weight functional polymer results from a chain transfer agent selected from the group consisting of polyacrylic acid, polylactic acid, polyphosphonic acid, polysulfonic acid, and polymaleic acid; and partially or fully neutralized and/or esterified forms of said acids; and combination thereof.

14. The sized reinforcing fiber of claim 11 , wherein the compatible functional non-fluorinated polymer is a functional acrylic copolymer including at least one methacrylic acid monomer and at least one methyl methacrylate monomer.

15. The sized reinforcing fiber of claim 11 , wherein the compatible functional non-fluorinated polymer includes at least one monomer selected from the group consisting of α,β unsaturated carboxylic acids, an acrylic monomer containing a hydroxyl group, a monomer containing an epoxy group, a monomer containing silanols, a monomer containing an aldehyde, an alkenyl cyanide, and acetoacetoxyethyl methacrylate.

16. A method of preparing sized carbon fiber comprising
1) Activating a carbon fiber to form oxygen or amine containing functional groups on the carbon fiber; and
2) Sizing the carbon fiber with a functionalized PVDF containing at least one functional group;
wherein the functionalized PVDF is a copolymer comprising copolymerized fluoromonomer and functional comonomer or is a functionalized block PVDF having a PVDF block and a low molecular weight functional polymer block, and is not grafted with maleic anhydride,
wherein the at least one functional group of the functionalized PVDF reacts with the functional group on the carbon fiber to form a bond with the carbon fiber.

1

Assignees

• Arkema Inc

Inventors

• O'Brien Gregory Scott
• Amin-Sanayei Ramin
• Zerafati Saeid
• Goldbach James T

Classifications

• D06M15/256 Primary

  containing fluorine · CPC title

• C08F214/22

  Vinylidene fluoride · CPC title

• C08F214/28

  Hexyfluoropropene · CPC title

• C08F220/06

  Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof · CPC title

• C08F220/18

  with acrylic or methacrylic acids · CPC title