Photocrosslinkable composition comprising a polyorganosiloxane

• US 20090226739A1
• Filed: 12/30/2008
• Published: 09/10/2009
• Est. Priority Date: 01/04/2008
• Status: Active Grant

• Current Assignee: Nexans Incorporated (Nokia Corporation)
• Original Assignee: Nexans Incorporated (Nokia Corporation)
• Inventors: Thivillon, Maud, Alric, Jerome, Pinto, Olivier
• Granted Patent: US 8,197,943 B2
• Time in Patent Office: Days
• US Class Current: 428/447
• CPC Class Codes: C08F 2/50 with sensitising agents
• CPC Class Codes: C08K 5/0025 Crosslinking or vulcanising agents; including accelerators
• CPC Class Codes: C08L 23/02 not modified by chemical after-treatment
• CPC Class Codes: C08L 23/12 Polypropene
• CPC Class Codes: C08L 2666/06 Homopolymers or copolymers of unsaturated hydrocarbons; Derivatives thereof
• CPC Class Codes: C08L 83/00 Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon only; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 83/04 Polysiloxanes
• CPC Class Codes: C08L 83/06 containing silicon bound to oxygen-containing groups C08L83/12 takes precedence
• CPC Class Codes: G02B 6/443 Protective covering
• CPC Class Codes: G02B 6/4436 Heat resistant
• CPC Class Codes: G02B 6/4486 Protective covering
• CPC Class Codes: G03F 7/0757 Macromolecular compounds containing Si-O, Si-C or Si-N bonds G03F7/0752 takes precedence
• CPC Class Codes: H01B 13/141 of two or more insulating layers
• CPC Class Codes: H01B 13/148 Selection of the insulating material therefor
• CPC Class Codes: H01B 3/46 silicones
• CPC Class Codes: H01B 7/295 using material resistant to flame
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane

Abstract

A photocrosslinkable composition has polyorganosiloxane P having a viscosity of at least 10 000 mPa·s at 25° C., wherein the polyorganosiloxane P has an acrylated silicone oil as a crosslinking agent, and a photoinitiator, the chemical structure of which comprises a diaryl ketone group.

Claims

1. A photocrosslinkable composition comprising:

a polyorganosiloxane P having a viscosity of at least 10 000 mPa·

s at 25°

C., said polyorganosiloxane P having an acrylated silicone oil as a crosslinking agent; and

a photoinitiator, the chemical structure of which includes a diaryl ketone group.

2. The composition as claimed in claim 1, wherein said polyorganosiloxane P is at most 40 parts by weight of said acrylated silicone oil per 100 parts by weight of polyorganosiloxane P.

5. The composition as claimed in claim 1, wherein the photoinitiator is chosen from benzophenone, dibenzosuberone, xanthone, anthrone, anthraquinone and derivatives thereof, or a mixture thereof.

6. The composition as claimed in claim 1, wherein the polyorganosiloxane is chosen from polyorganosiloxanes having a viscosity between 10 000 mPa·

s and 100 000 mPa·

s at 25°

C., and polyorganosiloxanes having a viscosity between 10 000 000 mPa·

s and 50 000 000 mPa·

s at 25°

C., or a mixture thereof.

7. The composition as claimed in claim 1, wherein the polyorganosiloxane P is a polydimethylsiloxane (PDMS).

8. The composition as claimed in claim 1, wherein the acrylated silicone oil has a viscosity between 100 and 1000 mPa·

s at 25°

C.

9. The composition as claimed in claim 1, wherein said polyorganosiloxane P includes at most 20 parts by weight of acrylated silicone oil per 100 parts by weight of polyorganosiloxane P.

10. The composition as claimed in claim 1, wherein said polyorganosiloxane P includes at most 10 parts by weight of photoinitiator per 100 parts by weight of polyorganosiloxane P.

11. The composition as claimed in claim 1, further comprising another initiator capable of generating free radicals under the effect of heat or actinic radiation.

12. The composition as claimed in claim 11, wherein the initiator capable of generating free radicals under the effect of heat is an organic peroxide.

13. The composition as claimed in claim 12, wherein initiator capable of generating free radicals under the effect of heat is at most 0.3 part by weight of organic peroxide per 100 parts by weight of polyorganosiloxane P.

14. The composition as claimed in claim 11, wherein the initiator capable of generating free radicals under the effect of actinic radiation is a Norrish type I photoinitiator.

15. An electric and/or optical cable comprising:

at least one crosslinked layer, wherein said layer is obtained from a photocrosslinkable composition as defined in claim 1.

16. The cable as claimed in claim 15, wherein said cable further comprises a filled polyolefin layer.

17. A method of manufacturing an electric and/or optical cable according to claim 15, said method comprising a step of:

i) irradiating the photocrosslinkable composition under actinic radiation to obtain the crosslinked layer.

18. The manufacturing method as claimed in claim 17, applied to an optical cable having a filled polyolefin layer, said method further comprising the step of:

following step i),

ii) bringing said crosslinked layer into contact with the filled polyolefin layer.

19. The manufacturing method as claimed in claim 17, wherein step i) is preceded by a step of extruding the photocrosslinkable composition.

3. A photocrosslinkable composition comprising:

a polyorganosiloxane P having a viscosity of at least 10 000 mPa·

s at 25°

C., said polyorganosiloxane P having at most 40 parts by weight of an acrylated silicone oil as a crosslinking agent per 100 parts by weight of polyorganosiloxane P; and

a photoinitiator capable of extracting a hydrogen atom from the polyorganosiloxane P when said photoinitiator is subjected to actinic radiation.

4. The composition as claimed in claim 3, wherein the chemical structure of said photoinitiator comprises a diaryl ketone group.