Modified fluoropolymers

Patent metadata

Field	Value
Publication number	US-2018072829-A1
Application number	US-201615557977-A
Country	US
Kind code	A1
Filing date	Mar 15, 2016
Priority date	Mar 16, 2015
Publication date	Mar 15, 2018
Grant date	—

Abstract

The invention relates to fluoropolymers that have been modified with low molecular weight, polymeric chain transfer agents, and uses of the modified fluoropolymers. The modified fluoropolymers provide enhanced properties to the fluoropolymer, such as increased adhesion, and hydrophilic characteristics. The modified functional fluoropolymers are useful in many applications, including as binders in electrode-forming compositions and separator compositions, for hydrophilic membranes and hollow fiber membranes, as an aqueous and a solvent cast coating for baked decorative and protective coatings, and as a tie layer between a fluoropolymer layer and an incompatible polymer layer.

First claim

1 . A modified fluoropolymer comprising fluoromonomer units and from 0.1 to 25 weight percent of residual functional groups, based on the total amount of monomer, wherein said residual functional groups in the modified fluoropolymer comprise residual functional groups from one or more low molecular weight polymeric functional chain transfer agents.

2 . The modified fluoropolymer of claim 1 , wherein said modified fluoropolymer comprises greater than 2 to 15 weight percent of said residual functional groups.

3 . The modified fluoropolymer of claim 1 , wherein said modified fluoropolymer comprises from 2.2 to 10 weight percent of said residual functional groups.

4 . The modified fluoropolymer of claim 1 , wherein said modified fluoropolymer comprises one or more fluoropolymer blocks and one or more blocks of said residual functional groups of the low molecular weight polymeric functional chain transfer agent.

5 . The modified fluoropolymer of claim 1 , wherein said low molecular weight polymeric functional chain transfer agents have molecular weights of less than 20,000 g/mole.

6 . The modified fluoropolymer of claim 1 , wherein said residual functional groups comprise a functionality selected from the group consisting of carboxylic, hydroxyl, siloxane, ester, ether, sulfonic, phosphoric, phosphonic, sulfuric, amide, and epoxy groups, or a mixture thereof.

7 . The modified fluoropolymer of claim 1 , wherein said fluoromonomer units are selected from the group consisting of vinylidene fluoride (VDF), vinyl fluoride (VF), trifluoroethylene, tetrafluoroethylene (TFE), ethylene tetrafluoroethylene, chlorotrifluoroethylene (CTFE) and hexafluoropropylene (HFP), 3,3,3-trifluoropropene, 2,3,3,3-tetrafluoropropene, ethylene and mixtures thereof.

8 . The modified fluoropolymer composition of claim 7 , wherein said fluoropolymer is a homopolymer of vinylidene fluoride or a copolymer of 71 to 99 weight percent vinylidene fluoride and 1 to 29 weight percent of one or more other fluoromonomers.

9 . A process for forming a functionalized fluoropolymer comprising the steps of
a) forming an aqueous emulsion comprising at least one radical initiator, at least one functional, low molecular weight polymeric chain transfer agent, at least one surfactant, and at least one fluoromonomer, and b) initiating polymerization of said at least one fluoromonomer, c) optionally adding a delayed feed comprising fluoromonomer, initiator and optionally low molecular weight polymeric functional chain transfer agent, and d) continuing polymerization to form a functionalized fluoropolymer.

10 . The process of claim 9 , wherein said process uses no fluorosurfactant.

11 . The process of claim 9 wherein said functional chain transfer agent is present in a total amount from about 0.1 to 25 weight percent based on total monomer.

12 . The process of claim 9 wherein said functional chain transfer agent is present in a total amount from more than 2.0 weight percent to 15 weight percent based on total monomer fed to the reactor.

13 . The process of claim 12 wherein said functional chain transfer agent is present in a total amount from 2.2 weight percent to 10 weight percent based on total monomer fed to the reactor.

14 . The process of claim 9 wherein said at least one fluoromonomer is selected from the group consisting of vinylidene fluoride (VDF), vinyl fluoride (VF), trifluoroethylene, tetrafluoroethylene (TFE), ethylene tetrafluoroethylene, chlorotrifluoroethylene (CTFE) and hexafluoropropylene (HFP), 3,3,3-trifluoropropene, 2,3,3,3-tetrafluoropropene, and mixtures thereof.

15 . The process of claim 9 , wherein said fluoropolymer is a homopolymer of vinylidene fluoride or a copolymer of 71 to 99 weight percent vinylidene fluoride and 1 to 29 weight percent of one or more other fluoromonomers.

16 . An article formed from the modified fluoropolymer of claim 1 .

17 . The article of claim 16 , wherein said article is selected from the group consisting of an electrode or separator component for a battery or capacitor; a porous membrane or hollow fiber membrane; an article coated on at least one surface with said modified fluoropolymer, and a multi-layer construction wherein said modified fluoropolymer forms a tie layer between a fluoropolymer layer and a polymer layer that is incompatible with said fluoropolymer layer.

18 . The modified fluoropolymer composition of claim 1 , wherein said modified fluoropolymer comprises 85 to 99.9 weight percent of a polyvinylidene fluoride homopolymer or copolymer center block polymer, and from 0.01 to 15 weight percent of poly(meth)acrylic acid block(s) at one or more ends of the polymer chain.

Assignees

• Arkema Inc

Inventors

• Amin-Sanayei Ramin
• He Wensheng
• Coffey James F
• Cavalier Chris
• Baxter Steven M
• Reynaud Sara

Classifications

• C08F114/22 Primary

  Vinylidene fluoride · CPC title

• C08F2/38

  Polymerisation using regulators, e.g. chain terminating agents {, e.g. telomerisation} · CPC title

• C08F214/222

  with fluorinated vinyl ethers · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title