Method of making adhesion between an optical waveguide structure and thermoplastic polymers

• US 9,770,862 B2
• Filed: 12/21/2015
• Issued: 09/26/2017
• Est. Priority Date: 09/10/2008
• Status: Active Grant

• Current Assignee: Kyton, LLC
• Original Assignee: Kyton, LLC
• Inventors: Swinehart, Philip R., Maklad, Mokhtar
• Primary Examiner(s): Jordan, Andrew
• Application Number:
  US14/977,050
• Publication Number:
  US 20160159000A1
• Time in Patent Office: 645 Days
• CPC Class Codes: B05D 3/002 Pretreatement
• CPC Class Codes: B29C 65/02 by heating, with or without pressure
• CPC Class Codes: B29D 11/00663 Production of light guides
• CPC Class Codes: B29D 11/00701 having an intermediate layer between core and cladding
• CPC Class Codes: B29K 2061/00 Use of condensation polymers of aldehydes or ketones or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2063/00 Use of EP, i.e. epoxy resins or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2077/00 Use of PA, i.e. polyamides, e.g. polyesteramides or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2079/08 PI, i.e. polyimides or derivatives thereof
• CPC Class Codes: B29K 2081/06 PSU, i.e. polysulfones; PES, i.e. polyethersulfones or derivatives thereof
• CPC Class Codes: B29L 2011/0075 Light guides, optical cables
• CPC Class Codes: G01K 11/3206 at discrete locations in the fibre, e.g. using Bragg scattering
• CPC Class Codes: G02B 6/0218 using mounting means, e.g. by using a combination of materials having different thermal expansion coefficients
• CPC Class Codes: G02B 6/02209 Mounting means, e.g. adhesives, casings G02B6/02171 and G02B6/02195 take precedence
• CPC Class Codes: G02B 6/02395 Glass optical fibre with a protective coating, e.g. two layer polymer coating deposited directly on a silica cladding surface during fibre manufacture G02B6/02052, G02B6/02057, G02B6/024, G02B6/032, G02B6/105, G02B6/14 take precedence; coating on fibre gratings G02B6/02104; multilayer core or cladding G02B6/036; reinforcing splice joints G02B6/2558; optical cables, i.e. comprising protective structures external to the protective coating such as a jacket or plural coated optical fibres G02B6/44; coating of glass to obtain optical fibres C03C25/104
• CPC Class Codes: G02B 6/36 Mechanical coupling means G02B6/255, G02B6/42 take precedence

Abstract

A compact method for forming strong hermetic bonds and seals. Such bonds are made simply and with no intervening adhesives, by directly melting a thermoplastic polymer against or between two surfaces of thermoset materials.

Claims

1. A method of obtaining strong adhesion between at least one optical waveguide structure and at least one thermoplastic polymer, the at least one optical waveguide structure being at least partially coated with at least one bonded thermoset polymer, the method comprising:

melting at least one thermoplastic polymer completely surrounding said thermoset coating in at least areas at which a bond is intended with the addition of a mechanical force provided by at least one force-applying member to create a bond or bonds between the at least one thermoplastic polymer and the at least one coating of thermoset polymer on the at least one optical waveguide structure, wherein

the bond formed is strong and adherent enough to form a hermetic seal between the at least one thermoset coating and the at least one thermoplastic polymer, and the temperature of the melting process is equal to or greater than the liquefaction temperature or temperature range of the at least one thermoplastic polymer and lower than the decomposition or carbon-forming temperature of the at least one thermoset polymer, and

employing at least one mold release material between a force-applying member and the thermoplastic polymer while molten.

2. The method according to claim 1, wherein

the mechanical force comprises one or both of an applied mechanical force or a force from an interference fit between at least one thermoplastic and at least one thermoset part.

3. The method according to claim 1, wherein

the at least one thermoplastic polymer comprises a polyether ether ketone polymer.

4. The method according to claim 1, wherein

the at least one thermoplastic polymer comprises a polyether ketone ketone polymer.

5. The method according to claim 1, wherein

the at least one thermoplastic polymer comprises a polyether-imide polymer.

6. The method according to claim 1, wherein

the at least one thermoplastic polymer comprises a polysulfone or polyether sulfone polymer.

7. The method according to claim 1, wherein

the at least one thermoset material comprises a polyimide polymer.

8. The method according to claim 1, wherein

the at least one thermoset material comprises a polyamide polymer.

9. The method according to claim 1, wherein

the at least one thermoset polymer comprises a polyamide-imide polymer.

10. The method according to claim 1, wherein

the at least one thermoset polymer comprises a cured or partially cured epoxy polymer.

11. The method according to claim 1, wherein

the at least one mold release material comprises a thermoset polymer with a decomposition temperature greater than the highest liquefaction temperature of the thermoplastic polymer(s) employed in the bond.

12. The method according to claim 1, wherein

the at least one mold release material comprises a thermoplastic polymer with a liquefaction temperature range greater than those of the other thermoplastic polymer(s) employed in the bond.

13. The method according to claim 1, wherein

the at least one mold release material comprises a silicone compound.

14. The method according to claim 1, wherein

the at least one mold release material comprises a fluorocarbon compound.

15. The method according to claim 1, wherein

the at least one thermoset polymer comprises at least the outermost layer of a buffer coating on a silica glass optical fiber.

16. The method according to claim 1, wherein

the at least one thermoset polymer comprises at least an outer layer of a buffer coating on an optical fiber followed by an extruded coating of a thermoplastic polymer.

17. The method according to claim 16, wherein

the optical fiber coating comprises a thermoplastic coating extruded or melted on top of an outer layer of a thermoset material that is the original outer layer of the fiber buffer coating on a silica glass optical fiber as drawn, prior to a further local melting of at least one additional thermoplastic part.

18. The method according to claim 1, wherein

said optical fiber is a silica glass optical fiber.

19. The method according to claim 1, wherein

the surfaces of either or both the thermoset and thermoplastic polymers to be bonded are treated with abrasive, chemical, plasma or corona means prior to bonding to enhance adhesion.

20. The method according to claim 1, wherein

the hermetic seal is made in at least one location on at least one optical fiber containing at least one interferometric optical device to form a hermetically sealed, suspended temperature sensor.

21. The method according to claim 20, wherein

the interferometric optical device is one or more of a fiber Bragg grating, a Fabry-Perot or a Michelson interferometer.

22. The method according to claim 1, wherein

the hermetic seal is made in at least one location on at least one optical fiber containing at least one interferometric optical device to form a hermetically sealed strain sensor.

23. The method according to claim 1, wherein

the hermetic seal is made on at least one optical fiber in at least one location to form a vacuum or pressure bulkhead feedthrough.

24. The method according to claim 1, wherein

the at least one mold release material comprises an inorganic material or a polymer that decomposes during the bonding process to an inorganic material with a melting range higher than the melting range of all said at least one thermoplastic polymer.

25. A method of obtaining a hermetic seal, comprising at least one layer or structure made of at least one thermoplastic material, between thermoplastic polymers and optical waveguides coated with at least one layer of a thermoset polymer, without the use of additional adhesives requiring chemical curing during employment of the method, wherein the optical waveguide comprises at least one structure that provides for the guiding of optical waves along the waveguide with a predetermined low loss of light power for a predetermined distance, the method comprising:

coating at least one surface of the optical waveguide structure with at least one layer of a thermoset polymer, followed by curing said thermoset polymer and

melting at least one structure of thermoplastic against said thermoset polymer with or without the addition of mechanical force.

26. The method according to claim 25, wherein

the waveguide comprises an optical fiber.

27. The method according to claim 25, wherein

the waveguide comprises an optical fiber with a light-guiding core possessing a higher index of refraction than a cladding material of nearly the same composition surrounding the core.

28. The method according to claim 27, wherein

the cladding material contains regions of gas or vacuum.

29. The method according to claim 25, wherein

the at least one waveguide is a planar waveguide.