Articles Produced from VDF-co-(TFE or TrFE) Polymers

Patent metadata

Field	Value
Publication number	US-10472491-B2
Application number	US-201715680555-A
Country	US
Kind code	B2
Filing date	Aug 18, 2017
Priority date	Jul 29, 2014
Publication date	Nov 12, 2019
Grant date	Nov 12, 2019

Abstract

VDF-co-(TFE or TrFE) polymers having a molecular weight of at least about 1,000,000 g/mol and a melt temperature less than about 240° C. The VDF copolymer contains at least about 50 mol % VDF monomer and may include an amount of at least one other monomer. The VDF copolymer may be used to form a membrane that has a node and fibril structure. The membrane has a percent porosity of at least 25%. A VDF-co-(TFE or TrFE) polymer membrane may be formed by lubricating the VDF copolymer, subjecting the lubricated polymer to pressure at a temperature below the melting point of the VDF copolymer to form a preform material, and expanding the preform material at a temperature below the melting temperature of the VDF copolymer. Dense VDF copolymer articles, filled VDF copolymer membranes, and VDF copolymer fibers are also provided.

First claim

What is claimed is:

1. A dense vinylidene fluoride (VDF) copolymer article comprising:
a vinylidene fluoride (VDF) copolymer membrane comprising a single VDF copolymer and having a porosity less than about 10%,
wherein said single VDF copolymer has a weight average molecular weight from about 1,000,000 g/mol to about 100,000,000 g/mol and about 50 mol % to about 85 mol % VDF monomers.

2. The dense article of claim 1 , wherein said VDF copolymer membrane has a matrix tensile strength in at least one direction greater than about 55 MPa.

3. The dense article of claim 2 in the form of a fiber.

4. The dense article of claim 1 , wherein said single VDF copolymer further comprises at least one comonomer in an amount from about 0.001 mol % to about 10 mol %.

5. The dense article of claim 1 , wherein said single VDF copolymer has a melt temperature that is less than about 240° C.

6. A process for making a dense vinylidene fluoride (VDF) copolymer article comprising:
calendering a vinylidene fluoride (VDF) copolymer membrane having about 50 mol % to about 85 mol % VDF monomer at a temperature less than the melt temperature of said VDF copolymer to form a dense VDF copolymer membrane,
wherein said VDF copolymer has a weight average molecular weight from about 1,000,000 g/mol to about 100,000,000 g/mol, and
wherein said dense VDF copolymer membrane has a porosity less than about 10%.

7. The process of claim 6 , wherein said calendering occurs in the absence of heat.

8. The process of claim 6 , wherein said calendering occurs at a temperature that is about 80° C. or less below the melt temperature of said VDF copolymer.

9. The process of claim 6 , wherein said melt temperature of said VDF copolymer is less than about 240° C.

10. The process of claim 6 , wherein said calendering occurs in the absence of a lubricant.

11. The process of claim 6 , wherein said calendering occurs in the presence of a lubricant.

12. The process of claim 6 , wherein said VDF copolymer further comprises at least one additional comonomer in an amount from about 0.001 mol % to about 10 mol %.

13. The process of claim 6 , further comprising expanding said dense VDF copolymer article to form an expanded dense VDF copolymer article.

14. The process of claim 6 , further comprising adding a filler material to said VDF copolymer.

15. The process of claim 6 , wherein said VDF copolymer membrane comprises a single VDF copolymer.

Assignees

• Gore & Ass

Inventors

• Sbriglia Guy A
• Shafer Gregory J

Classifications

• B01D71/34

  Polyvinylidene fluoride · CPC title

• D01F6/32

  comprising halogenated hydrocarbons as the major constituent · CPC title

• B29C55/02

  of plates or sheets · CPC title

• B29K2105/25

  Solid · CPC title

• B01D71/76

  Macromolecular material not specifically provided for in a single one of groups B01D71/08 - B01D71/74 (rubbers in general B01D71/24) · CPC title