Multilayer flexible tube and methods for making same

Patent metadata

Field	Value
Publication number	US-10295089-B2
Application number	US-201715582068-A
Country	US
Kind code	B2
Filing date	Apr 28, 2017
Priority date	Mar 10, 2014
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

A multilayer flexible tube includes an inner layer including a melt processable fluoropolymer, wherein the fluoropolymer includes a copolymer of a poly vinylidene fluoride (PVDF) and a hexafluoropropylene (HFP); and an outer layer including a melt processable polymer having a shore hardness less than a shore hardness of the inner layer, wherein the multilayer flexible tube has a maximum storage modulus of at least 300 MegaPascal (MPa) at a temperature of about −10° C.

First claim

What is claimed is:

1. A multilayer flexible tube comprising:
an inner layer comprising a melt processable fluoropolymer, wherein the fluoropolymer comprises a copolymer consisting essentially of a poly vinylidene fluoride (PVDF) and a hexafluoropropylene (HFP); and
an outer layer directly in contact with the inner layer, the outer layer comprising a melt processable polymer having a shore hardness less than a shore hardness of the inner layer, wherein the multilayer flexible tube has a maximum storage modulus of at least 300 MegaPascal (MPa) at a temperature of about −10° C.

2. The multilayer flexible tube of claim 1 , wherein the maximum storage modulus is at least 300 MegaPascal (MPa) at a temperature of about −20° C.

3. The multilayer flexible tube of claim 1 , having less than a 50% loss in deflection at a temperature of 23° C. to −18° C.

4. The multilayer tube of claim 1 , wherein the molar ratio of the poly vinylidene fluoride to the hexafluoropropylene in the copolymer is 1:99 to 99:1.

5. The multilayer flexible tube of claim 1 , wherein the copolymer of the poly vinylidene fluoride and the hexafluoropropylene has a shore D of less than about 95.

6. The multilayer flexible tube of claim 1 , wherein the melt processable polymer of the outer layer comprises a thermoplastic polyurethane, a thermoset urethane, a fluoroelastomer, EPDM, a thermoplastic EPDM composite, a styrene-ethylene based copolymer, a styrene isoprene based copolymer, a polyolefin elastomer, a PVC, an isoprene, a thermoplastic isoprene composite, or a blend, an alloy, or any combination thereof.

7. The multilayer flexible tube of claim 6 , wherein the melt processable polymer of the outer layer comprises a thermoplastic polyurethane, a PVC, or an alloy, or combination thereof.

8. The multilayer flexible tube of claim 1 , wherein the outer layer has a shore A hardness of less than about 80.

9. The multilayer flexible tube of claim 1 , wherein the flexible tube has a resistance to fuel permeation of less than about 15 g/day/m 2 , when measured by SAE J30 and SAE J1737.

10. The multilayer flexible tube of claim 1 , wherein the inner layer and the outer layer are resistant to layer separation after exposure to fuel after at least 2 weeks at 110° F.

11. The multilayer flexible tube of claim 1 , wherein the multilayer flexible tube is a fuel tube, a peristaltic pump tube, or a chemically resistant liquid transfer tube.

12. The multilayer flexible tube of claim 1 , wherein the inner layer, the outer layer, or combination thereof further comprises a co-agent.

13. The multilayer flexible tube of claim 12 , wherein the co-agent comprises bis-phenol AF, triaryl isocyanurate (TAIL), Triaryl cyanurate (TAC), an organic peroxide, or combination thereof.

14. The multilayer flexible tube of claim 12 , wherein the multilayer flexible tube is irradiated.

15. A multilayer flexible tube comprising:
an inner layer comprising a melt processable fluoropolymer, wherein the fluoropolymer comprises a copolymer of a poly vinylidene fluoride (PVDF) and a hexafluoropropylene (HFP);
an outer layer comprising a melt processable polymer having a shore hardness less than a shore hardness of the inner layer; and
a tie layer disposed between the inner layer and the outer layer, wherein the tie layer comprises a blend of a thermoplastic urethane with a fluoropolymer copolymer of hexafluoropropylene and poly vinylidene fluoride, wherein the multilayer flexible tube has a maximum storage modulus of at least 300 MegaPascal (MPa) at a temperature of about −10° C.

16. The multilayer flexible tube of claim 15 , wherein the melt processable polymer of the outer layer is a thermoplastic polyurethane, a thermoset urethane, a fluoroelastomer, EPDM, a thermoplastic EPDM composite, a styrene-ethylene based copolymer, a styrene isoprene based copolymer, a polyolefin elastomer, a PVC, an isoprene, a thermoplastic isoprene composite, or a blend, an alloy, or any combination thereof.

17. The multilayer flexible tube of claim 15 , wherein the tie layer further comprises an adhesion promoter, the adhesion promoter comprising a maleic anhydride grafted PVDF, a silane-based adhesion promoter, an epoxy-based chemical, an EVOH, acrylate polymer, an acrylate copolymer, an acetal copolymer, a thermoplastic with polarity, or combination thereof.

Assignees

• Saint Gobain Performance Plastics Corp

Inventors

• Garver Wayne Edward
• Ludlow James
• Ling Gerald H
• Golub Charles S
• Morris Kathryn J
• Colton Mark F

Classifications

• B32B2250/24

  All layers being polymeric · CPC title

• B29C47/065

  Operations & Transport · mapped topic

• B32B27/34

  comprising polyamides · CPC title

• B32B2597/00

  Tubular articles, e.g. hoses, pipes · CPC title

• B32B27/304

  comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF · CPC title