Tube based on vulcanized elastomer and fluoropolymer

• US 20020106470A1
• Filed: 12/11/2001
• Published: 08/08/2002
• Est. Priority Date: 12/11/2000
• Status: Abandoned Application

• Current Assignee: ATOFINA Chemicals, Inc. (Arkema)
• Original Assignee: ATOFINA Chemicals, Inc. (Arkema)
• Inventors: Merziger, Joachim, Maldeme, Christophe
• Application Number:
  US10/012,044
• Publication Number:
  US 20020106470A1
• Time in Patent Office: Days
• US Class Current: 428/36.91
• CPC Class Codes: B32B 1/08 Tubular products
• CPC Class Codes: C08F 297/026 polymerising acrylic acid, methacrylic acid or derivatives thereof
• CPC Class Codes: C08F 297/048 polymerising vinyl aromatic monomers, conjugated dienes and polar monomers
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 2666/24 Graft or block copolymers according to groups C08L51/00, C08L53/00 or C08L55/02; Derivatives thereof
• CPC Class Codes: C08L 27/16 Homopolymers or copolymers or vinylidene fluoride
• CPC Class Codes: C08L 53/00 Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
• CPC Class Codes: F16L 11/127 electrically conducting
• CPC Class Codes: Y10T 428/1393 Multilayer [continuous layer]

Abstract

The present invention relates to a tube having in its radial direction, from the inside outwards:

1) a so-called inner layer intended to come into contact with a circulating fluid, the said inner layer comprising (i) a fluoropolymer, (ii) optionally an electrically conductive product and (iii) a triblock copolymer ABC, the three blocks A, B, and C being linked together in this order, each block being either a homopolymer or a copolymer obtained from two or more monomers, the block A being linked to the block B and the block B to the block C by means of a covalent bond or an intermediate molecule linked to one of these blocks via a covalent bond and to the other block via another covalent bond, and such that:

block A is compatible with the fluoropolymer,

block B is incompatible with the fluoropolymer and is incompatible with block A,

block C is incompatible with the fluoropolymer, block A and block B,

2) optionally, a binder layer,

3) a layer of vulcanized elastomer.

According to a second form of the invention the inner layer itself consists of two layers, one containing an electrically conductive product and the other containing no electrically conductive product. Advantageously, the layer which is in contact with the circulating fluid contains the electrically conductive product.

According to a third form of the invention a layer of fluoropolymer is provided between the inner layer and the binder layer or between the inner layer and the layer of vulcanized elastomer if there is no binder.

The second and third forms of the invention may exist simultaneously for the same tube.

Claims

1. Tube having in its radial direction, from the inside outwards:

1) a so-called inner layer intended to come into contact with a circulating fluid, the said inner layer comprising (i) a fluoropolymer, (ii) optionally an electrically conductive product and (iii) a triblock copolymer ABC, the three blocks A, B, and C being linked together in this order, each block being either a homopolymer or a copolymer obtained from two or more monomers, the block A being linked to the block B and the block B to the block C by means of a covalent bond or an intermediate molecule linked to one of these blocks via a covalent bond and to the other block via another covalent bond, and such that;

block A is compatible with the fluoropolymer,

block B is incompatible with the fluoropolymer and is incompatible with block A,

block C is incompatible with the fluoropolymer, block A and block B,

2) optionally, a binder layer,

3) a layer of vulcanized elastomer.

2. Tube according to claim 1, in which the fluoropolymer of the inner layer is a PVDF homopolymer or copolymer.

3. Tube according to claim 1 or 2, in which the electrically conductive product of the inner layer is chosen from graphite, carbon black, carbon nanotubes and carbon fibers.

4. Tube according to claim 3, in which the electrically conductive product is carbon black with a nitrogen adsorption surface of less than 500 m²/g.

5. Tube according to claim 4, in which the surface area is less than 100 m²/g.

6. Tube according to any one of the preceding claims, in which the triblock copolymer ABC of the inner layer is poly (methyl methacrylate-b-butadiene-b-styrene).

7. Tube according to any one of the preceding claims, in which the number-average molecular mass (M_n) of the triblock copolymer ABC of the inner layer is greater than or equal to 20 000 g.mol⁻

1, and preferably between 50 000 and 20 000 g.mol<sup>−

1</sup>.

8. Tube according to any one of the preceding claims, in which the proportions are, by weight, in the inner layer:

65 to 97% of fluoropolymer,

0 to 25% of electrically conductive product,

3 to 15% of triblock coplymer ABC.

9. Tube according to claim 8, in which the proportions are, by weight:

65 to 92% of fluoropolymer,

5 to 25% of electrically conductive product,

3 to 15% of triblock copolymer ABC.

10. Tube according to any one of the preceding claims, in which the inner layer itself consists of two layers, one containing an electrically conductive product and the other containing no electrically conductive product.

11. Tube according to any one of the preceding claims, in which a layer of fluoropolymer is provided between the inner layer and the binder layer or between the inner layer and the layer of vulcanized elastomer, if there is no binder.