Crosslinkable rubber compositions and use thereof

• US 6,864,315 B1
• Filed: 03/14/2000
• Issued: 03/08/2005
• Est. Priority Date: 03/16/1999
• Status: Expired due to Term

• Current Assignee: Mitsui Chemicals Incorporated (Mitsui Chemicals), Shin-Etsu Chemical Company Limited
• Original Assignee: Mitsui Chemicals Incorporated (Mitsui Chemicals), Shin-Etsu Chemical Company Limited
• Inventors: Kameda, Hiroshi, Nonaka, Shuichi, Ishii, Yuji, Koda, Taku, Nakahama, Hidenari, Kawasaki, Masaaki, Nakamura, Tsutomu, Hosoya, Mikio, Yoshida, Takeo, Hakuta, Takashi, Kikuchi, Yoshiharu, Arino, Mitsunao, Hirabayashi, Satao
• Primary Examiner(s): Lipman, Bernard
• Application Number:
  US09/673,608
• Time in Patent Office: 1,820 Days
• Field of Search: 525/105
• US Class Current: 525/105
• CPC Class Codes: C08K 5/0025 Crosslinking or vulcanising agents; including accelerators
• CPC Class Codes: C08L 23/16 Elastomeric ethene-propene or ethene-propene-diene copolymers, e.g. EPR and EPDM rubbers
• CPC Class Codes: C08L 2312/08 by silane
• CPC Class Codes: C08L 2314/02 Ziegler natta catalyst
• 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

Abstract

The crosslinkable rubber composition of the invention is crosslinkable by hot air, and a hot-air crosslinked rubber sheet thereof has no scratch on the surface in a hardness test using a pencil of HB and has a compression set of not more than 70% after a heat treatment at 150° C. for 22 hours. The rubber composition comprises an ethylene/α-olefin/non-conjugated polyene random copolymer rubber comprising a specific vinyl end group-containing norbornene compound, a SiH group-containing compound having at least two SiH groups in one molecule, and if necessary, an addition reaction catalyst comprising a platinum group element and a reaction inhibitor. The automobile weatherstrip, hose, rubber vibration insulator, belt, sealing material, expanded product, covered electric wire, electric wire joint, electric insulating part and household rubber product according to the invention comprise the above-mentioned rubber composition. The rubber composition has a high crosslinking rate and excellent productivity to produce crosslinked rubber molded products, is capable of undergoing hot-air crosslinking such as HAV or UHF and is capable of providing crosslinked rubber molded products having excellent compression set resistance, strength properties, heat resistance, weathering resistance and abrasion resistance.

Claims

1. A crosslinkable rubber composition, which is crosslinkable by hot air and has the following properties:

a crosslinked rubber sheet obtained by molding said rubber composition into a sheet and then subjecting the sheet to hot-air crosslinking has no scratch on the surface in a pencil hardness test using a pencil of HB and has a compression set (CS) of not more than 70% after a heat treatment at 150°

C. for 22 hours, and further comprises;

an ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) having constituent units derived from at least one kind of a vinyl end group-containing norbornene compound represented by the following formula (I) or (II), said norbornene compound being the non-conjugated polyene, and

a SiH group-containing compound (B) having at least two SiH groups in one molecule;

wherein n is an integer of 0 to 10, R¹ is a hydrogen atom or an alkyl group of 1 to 10 carbon atoms, and R² is a hydrogen atom or an alkyl group of 1 to 5 carbon atoms;

wherein R³ is a hydrogen atom or an alkyl group of 1 to 10 carbon atoms.

2. The crosslinkable rubber composition as claimed in claim 1, which comprises the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A), the SiH group-containing compound (B) having at least two SiH groups in one molecule, and a catalyst (E).

3. The crosslinkable rubber composition as claimed in claim 1, which comprises the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A), the SiH group-containing compound (B) having at least two SiH groups in one molecule, a catalyst (E) and a reaction inhibitor (F).

4. The crosslinkable rubber composition as claimed in claim 1, wherein the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has the following properties;

(i) the molar ratio (ethylene/α

-olefin) of ethylene to an α

-olefin of 3 to 20 carbon atoms is in the range of 40/60 to 95/5,

(ii) the iodine value is in the range of 0.5 to 50, and

(iii) the intrinsic viscosity (η

) as measured in Decalin at 135°

C. is in the range of 0.3 to 10 dl/g.

9. The crosslinkable rubber composition as claimed in claim 2, wherein the catalyst (E) is a platinum catalyst.

11. The crosslinkable rubber composition as claimed in any one of claims 1 to 9 , which has a crosslinking rate (t_c(90)) at 160°

C. of not more than 15 minutes.

12. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which comprises

an ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A1) having constituent units derived from at least one kind of a vinyl end group-containing norbornene compound represented by the following formula (I) or (II), said norbornene compound being the non-conjugated polyene, and constituent units derived from a non-conjugated polyene compound (2) containing a group represented by the following formula (III); and

the SiH group-containing compound (B) having at least two SiH groups in one molecule;

wherein n is an integer of 0 to 10, R¹ is a hydrogen atom or an alkyl group of 1 to 10 carbon atoms, and R² is a hydrogen atom or an alkyl group of 1 to 5 carbon atoms;

wherein R³ is a hydrogen atom or an alkyl group of 1 to 10 carbon atoms;

wherein R⁴ is an alkyl group of 1 to 10 carbon atoms, and R⁵ and R⁶ are each independently a hydrogen atom or an alkyl group of 1 to 10 carbon atoms.

13. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, wherein the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) is the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A1) and has the following properties;

(i) the molar ratio (ethylene/α

-olefin) of ethylene to an α

-olefin of 3 to 20 carbon atoms is in the range of 40/60 to 95/5,

(ii) the iodine value is in the range of 0.5 to 50,

(iii) the intrinsic viscosity (η

) as measured in Decalin at 135°

C. is in the range of 0.3 to 10 dl/g, and

(iv) the branch index as measured by a kinematic viscoelasticity measuring machine is not less than 5.

14. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a blend comprising the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A), a polyolefin resin (D1) and the SiH group-containing compound (B), is obtained by microdispersing the polyolefin resin (D1) in the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) in a molten state, and has the following properties;

the average dispersed particle diameter of the polyolefin resin (D1) is not more than 2 μ

m, and

the blending weight ratio ((D1)/(A)) of the polyolefin resin (D1) to the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) is in the range of 5/95 to 50/50.

15. The crosslinkable rubber composition as claimed in claim 14, which is a blend comprising the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A), a polyolefin resin (D1) selected from crystalline homopolymers of α

-olefin having 3 to 8 carbon atoms and crystalline α

-olefin copolymers of said α

-olefins and the SiH group-containing compound (B), is obtained by microdispersing the polyolefin resin (D1) in the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) in a molten state, and has the following properties;

the average dispersed particle diameter of the polyolefin resin (D1) is not more than 2 μ

m,

the blending weight ratio ((D1)/(A)) of the polyolefin resin (D1) to the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) is in the range of 5/95 to 50/50, and

the hardness (Y) (A hardness defined by JIS K

     6301) of said rubber composition and the amount (X) of the polyolefin resin (D1) satisfy the following relation

Y=(0.5±

0.2)X+a

wherein X is an amount (part(s) by weight, the total of the components (A) and (D) is 100 parts by weight) of the polyolefin resin (D1), and a is a hardness obtained by subtracting an increase of hardness attributed to the addition of the polyolefin resin (D1) from the hardness of the rubber composition).

16. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, wherein the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has the following properties;

(i) the molar ratio (ethylene/α

-olefin) of ethylene to an α

-olefin of 3 to 20 carbon atoms is in the range of 40/60 to 95/5,

(ii) the iodine value is in the range of 0.5 to 50,

(iii) the intrinsic viscosity (η

) as measured in Decalin at 135°

C. is in the range of 0.3 to 10 dl/g, and

(iv) the branch index as measured by a kinematic viscoelasticity measuring machine is not less than 5.

17. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which further comprises an alkenyl group-containing organopolysiloxane (C) in addition to the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) and the SiH group-containing compound (B).

18. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, wherein the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has the following properties;

(i) the molar ratio (ethylene/α

-olefin) of ethylene to an α

-olefin of 3 to 20 carbon atoms is in the range of 40/60 to 95/5,

(ii) the iodine value is in the range of 0.5 to 50,

(iii) the intrinsic viscosity (η

) as measured in Decalin at 135°

C. is in the range of 0.3 to 10 d/g, and

(iv) the branch index as measured by a kinematic viscoelasticity measuring machine is not less than 5.

19. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is crosslinkable by hot air and has the following properties:

a hot-air crosslinked rubber sheet obtained by molding said rubber composition into a sheet and then subjecting the sheet to hot-air crosslinking has no scratch on the surface in a pencil hardness test using a pencil of HB and has a compression set (CS) of not more than 70% after a heat treatment at 150°

C. for 22 hours and a tensile strength retention of 50 to 300% after heat aging at 150°

C. for 72 hours.

20. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for producing an automobile weatherstrip.

21. The crosslinkable rubber composition as claimed in claim 20, wherein the automobile weatherstrip is a door weatherstrip, a trunk weatherstrip, a luggage weatherstrip, a roof side rail weatherstrip, a slide door weatherstrip, a ventilator weatherstrip, a sliding loop panel weatherstrip, a front window weatherstrip, a rear window weatherstrip, a quarter window weatherstrip, a lock pillar weatherstrip, a door glass outer weatherstrip, a door glass inner weatherstrip, a dam windshield, a glass run channel, a door mirror bracket, a seal head lamp or a seal cowl top.

22. An automobile weatherstrip formed from the crosslinkable rubber composition of any one of claims 1 to 9.

23. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a rubber composition for glass run that is crosslinkable by hot air and a hot press and which has the following properties:

a hot-press crosslinked rubber sheet obtained by molding said rubber composition into a sheet and then subjecting the sheet to hot-press crosslinking has a tensile strength of 5 to 16 MPa and a compression set (CS) of not more than 70% after a heat treatment at 150°

C. for 22 hours.

24. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a crosslinkable rubber composition for glass run and in which the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has the following properties;

(i) the molar ratio (ethylene/α

-olefin) of ethylene to an α

-olefin of 3 to 20 carbon atoms is in the range of 60/40 to 80/20,

(ii) the iodine value is in the range of 1 to 30,

(iii) the intrinsic viscosity (η

) as measured in Decalin at 135°

C. is in the range of 1.5 to 3.5 dl/g, and

(iv) the branch index as measured by a kinematic viscoelasticity measuring machine is not less than 5.

26. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for producing an automobile hose, a water supply hose or a gas hose.

27. The crosslinkable rubber composition as claimed in claim 26, wherein the automobile hose is a brake hose, a radiator hose, a heater hose or an air cleaner hose.

28. A hose formed from the crosslinkable rubber composition of any one of claims 1 to 9.

29. The hose as claimed in claim 28, which is an automobile hose, a water supply hose or a gas hose.

30. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a rubber composition for hose that is crosslinkable by hot air and a hot press and which has the following properties:

a hot-press crosslinked rubber sheet obtained by molding said rubber composition into a sheet and then subjecting the sheet to hot-press crosslinking has a volume resistivity (23°

C.) of 10³ to 10¹⁶ Ω

·

cm, a tensile strength of 5 to 30 MPa and a compression set (CS) of not more than 70% after a heat treatment at 150°

C. for 22 hours.

31. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a crosslinkable rubber composition for hose and in which the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has the following properties;

(i) the molar ratio (ethylene/α

-olefin) of ethylene to an α

-olefin of 3 to 20 carbon atoms is in the range of 60/40 to 80/20.

(ii) the iodine value is in the range of 1 to 30,

(iii) the intrinsic viscosity (η

) as measured in Decalin at 135°

C. is in the range of 0.3 to 5.0 dl/g, and

(iv) the branch index as measured by a kinematic viscoelasticity measuring machine is not less than 5.

32. A hose comprising the rubber composition of claim 30.

33. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for producing an automobile rubber vibration insulator, a railway rubber vibration insulator, an industrial equipment rubber vibration insulator or an earthquake proof rubber for construction.

34. The crosslinkable rubber composition as claimed in claim 33, wherein the automobile rubber vibration insulator is an engine mount, a liquid seal engine mount, a damper pulley, a chain damper, a carburetor mount, a torsional damper, a strut mount, a rubber bush, a bumper rubber, a helper rubber, a spring sheet, a shock absorber, an air spring, a body mount, a bumper guard, a muffler support, a rubber coupling, a center bearing support, a clutch rubber, a deaf mount, a suspension bush, a slide bush, a cushion strut bar, a stopper, a handle damper, a radiator supporter or a muffler hanger.

35. The crosslinkable rubber composition as claimed in claim 33, wherein the railway rubber vibration insulator is a slab mat, a ballast mat or a track mat.

36. The crosslinkable rubber composition as claimed in claim 33, wherein the industrial equipment rubber vibration insulator is an expansion joint, a flexible joint, a bush or a mount.

37. A rubber vibration insulator comprising the crosslinkable rubber composition of any one of claims 1 to 9.

38. The rubber vibration insulator as claimed in claim 37, which is an automobile rubber vibration insulator, a railway rubber vibration insulator, an industrial equipment rubber vibration insulator or an earthquake proof rubber for construction.

39. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a rubber composition for rubber vibration insulator that is crosslinkable by hot air and a hot press and which has the following properties:

a hot-press crosslinked rubber sheet obtained by molding said rubber composition into a sheet and then subjecting the sheet to hot-press crosslinking has a tensile strength of 5 to 16 MPa and a compression set (CS) of not more than 70% after a heat treatment at 150°

C. for 22 hours.

40. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a crosslinkable rubber composition for rubber vibration insulator and in which the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has the following properties;

(i) the molar ratio (ethylene/α

-olefin) of ethylene to an α

-olefin of 3 to 20 carbon atoms is in the range of 60/40 to 80/20,

(ii) the iodine value is in the range of 1 to 30,

(iii) the intrinsic viscosity (η

) as measured in Decalin at 135°

C. is in the range of 1.5 to 3.5 dl/g, and

(iv) the branch index as measured by a kinematic viscoelasticity measuring machine is not less than 5.

41. A vibration insulating rubber product formed from the rubber composition of claim 39.

42. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for producing a transmission belt or a conveyor belt.

43. The crosslinkable rubber composition as claimed in claim 42, wherein the transmission belt is a V-belt, A flat bell or a synchronous belt.

44. The crosslinkable rubber composition as claimed in claim 42, wherein the conveyor belt is a light conveyor belt, a cylindrical belt, a rough top belt, a flanged conveyor belt, a U-type guided conveyor belt or a V guided conveyor belt.

45. A belt formed from the crosslinkable rubber composition of any one of claims 1 to 9.

46. The belt as claimed in claim 45, which is a transmission belt or a conveyor belt.

47. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for producing an automobile cup/sealing material or an industrial equipment sealing material.

48. The crosslinkable rubber composition as claimed in claim 47, wherein the automobile cup/sealing material is a master cylinder piston cup, a wheel cylinder piston cup, a uniform motion joint boot, a pin boot, a dust cover, a piston seal, a packing, an O-ring or a diaphragm.

49. The crosslinkable rubber composition as claimed in claim 47, wherein the industrial equipment sealing material is a condenser packing, an O-ring or a packing.

50. A sealing material formed from the crosslinkable rubber composition of any one of claims 1 to 9.

51. The sealing material as claimed in claim 50, which is an automobile cup/sealing material or an industrial equipment sealing material.

52. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for producing an automobile weatherstrip sponge or another expanded product.

53. The crosslinkable rubber composition as claimed in claim 52, wherein the automobile weatherstrip sponge is a door weatherstrip sponge, a bonnet weatherstrip sponge, a trunk room weatherstrip sponge, a sunshine roof weatherstrip sponge, a ventilator weatherstrip sponge or a corner sponge.

54. The crosslinkable rubber composition as claimed in claim 52, wherein the another expanded product is a hose-protecting sponge, a cushioning sponge, a heat insulating sponge or an insulation pipe.

55. An expanded product formed from the crosslinkable rubber composition of any one of claims 1 to 9.

56. The expanded product as claimed in claim 55, which is an automobile weatherstrip sponge.

57. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a rubber composition for weatherstrip sponge that is crosslinkable by hot air and which has the following properties:

a crosslinked rubber sheet obtained by molding said rubber composition into a sheet and then subjecting the sheet to hot-air crosslinking has a specific gravity of 0.1 to 0.8 and a water absorption of not more than 50%.

58. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a rubber composition for weatherstrip sponge and in which the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has the following properties;

(i) the molar ratio (ethylene/α

-olefin) of ethylene to an α

-olefin of 3 to 20 carbon atoms is in the range of 60/40 to 90/10,

(ii) the iodine value is in the range of 1 to 30,

(iii) the intrinsic viscosity (η

)as measured in Decalin at 135°

C. is in the range of 0.3 to 5 dl/g, and

(iv) the branch index as measured by a kinematic viscoelasticity measuring machine is not less than 3.

59. A weatherstrip sponge formed from the crosslinkable rubber composition of any one of claims 1 to 9.

60. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a rubber composition for highly expanded sponge that is crosslinkable by hot air and which has the following properties:

an expanded product of a crosslinked rubber sheet obtained by molding said rubber composition into a sheet and then subjecting the sheet to hot-air crosslinking has a specific gravity of 0.01 to 0.5, a water absorption of 1 to 500% and an Asker C hardness of 0.1 to 50.

61. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a crosslinkable rubber composition for highly expanded sponge and in which the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has the following properties;

(i) the molar ratio (ethylene/α

-olefin) of ethylene to an α

-olefin of 3 to 20 carbon atoms is in the range of 60/40 to 90/10,

(ii) the iodine value is in the range of 1 to 30,

(iii) the intrinsic viscosity (η

) as measured in Decalin at 135°

C. is in the range of 0.3 to 4 dl/g, and

(iv) the branch index as measured by a kinematic viscoelasticity measuring machine is not less than 5.

62. A highly expanded sponge formed from the rubber composition of any one of claims 1 to 9.

63. The highly expanded sponge as claimed in claim 62, which is a heat insulating sponge, a cushioning sponge, a sealing sponge or a flame-retardant sponge.

64. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for producing a covered electric wire, an electric wire joint or an electric insulating part.

65. A covered electric wire covered with a covering material comprising the crosslinkable rubber composition of any one of claims 1 to 9.

66. An electric wire joint formed from the crosslinkable rubber composition of any one of claims 1 to 9.

68. A semi-conducting rubber part formed from the crosslinkable rubber composition of any one of claims 1 to 9.

69. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a rubber composition for electric or electronic part that is crosslinkable by hot air and a hot press and which has the following properties:

a hot-press crosslinked rubber sheet obtained by molding said rubber composition into a sheet and then subjecting the sheet to hot-press crosslinking has a volume resistivity (23°

C.) of 10⁷ to 10¹⁷ Ω

·

cm, a tensile strength of 3 to 20 MPa and a compression set (CS) of not more than 70% after a heat treatment at 150°

C. for 22 hours.

70. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is a crosslinkable rubber composition for electric or electronic part and in which the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has the following properties;

(i) the molar ratio (ethylene/α

-olefin) of ethylene to an α

-olefin of 3 to 20 carbon atoms is in the range of 60/40 to 90/10,

(ii) the iodine value is in the range of 1 to 30,

(iii) the intrinsic viscosity (η

) as measured in Decalin at 135°

C. is in the range of 0.3 to 2.5 dl/g, and

(iv) the branch index as measured by a kinematic viscoelasticity measuring machine is not less than 5.

71. An electric or electronic part formed from the crosslinkable rubber composition of any one of claims 1 to 9.

72. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for producing a household rubber product.

73. The crosslinkable rubber composition as claimed in claim 72, wherein the household rubber product is rain wear, rubber band, shoe, rubber glove, latex or golf ball.

74. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which can be crosslinked at ordinary temperature.

75. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for reaction injection molding (RIM).

76. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for producing a thermoplastic elastomer.

77. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for modifying an engineering plastic.

78. A household rubber product formed from the crosslinkable rubber composition of any one of claims 1 to 9.

79. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for producing a sealing sponge for construction.

80. The crosslinkable rubber composition as claimed in claim 79, wherein the sealing sponge for construction is a sealing sponge for gasket, airtight, joint or door stop.

81. The expanded product as claimed in claim 55, which is a sealing sponge for construction.

82. The crosslinkable rubber composition as claimed in any one of claims 1 to 9, which is used for producing an OA machine roll or an industrial roll.

83. The crosslinkable rubber composition as claimed in claim 82, wherein the OA machine roll is an electric charge roll, a transfer roll, a developing roll or a paper feed roll.

84. The crosslinkable rubber composition as claimed in claim 82, wherein the industrial roll is an iron manufacturing roll, a paper manufacturing roll or a printing electric wire roll.

85. An OA machine roll comprising the crosslinkable rubber composition of any one of claims 1 to 9.

86. An industrial roll formed from the crosslinkable rubber composition of any one of claims 1 to 9.

87. A hose comprising the rubber composition of claim 31.

88. A vibration insulating rubber product formed from the rubber composition of claim 40.

5. A crosslinkable rubber composition which comprises:

an ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) having constituent units derived from at least one kind of a vinyl end group-containing norbornene compound represented by the following formula (I) or (II), said norbornene compound being the non-conjugated polyene, and

a SiH group-containing compound (B) having at least two SiH groups in one molecule;

wherein n is an integer of 0 to 10, R¹ is a hydrogen atom or an alkyl group of 1 to 10 carbon atoms, and R² is a hydrogen atom or an alkyl group of 1 to 5 carbon atoms;

wherein R³ is a hydrogen atom or an alkyl group of 1 to 10 carbon atoms, wherein the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has the following properties;

(i) the molar ratio (ethylene/α

-olefin) of ethylene to an α

-olefin of 3 to 20 carbon atoms is in the range of 40/60 to 95/5,

(ii) the iodine value is in the range of 0.5 to 50,

(iii) the intrinsic viscosity (η

) as measured in Decalin at 135°

C. is in the range of 0.3 to 10 dl/g,

(iv) the molecular weight distribution (Mw/Mn) as measured by GPC is in the range of 3 to 50, and

(v) the effective network chain density (ν

) as measured after the copolymer rubber (A) is press crosslinked at 170°

C. for 10 minutes using 0.01 mol of dicumyl peroxide based on 100 g of the copolymer rubber (A) is not less than 1.5×

10²⁰ chains/cm³.

6. The crosslinkable rubber composition as claimed in claim 5, wherein the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has, in addition to the properties (i), (ii), (iii), (iv) and (v), the following properties;

(vi) the ratio between a ratio (γ

₂/γ

₁) of a shear rate γ

₂ at a shear stress of 2.4×

10⁶ dyn/cm² obtained from the melt flow curve at 100°

C. to a shear rate γ

₁ at a shear stress of 0.4×

10⁶ dyn/cm² obtained from the melt flow curve at 100°

C. and the effective network chain density (ν

) satisfies the following formula (III);

0.04×

10<sup>−

19</sup>≦

Log(γ

₂/γ

₁)/ν

≦

0.20×

10<sup>−

19</sup> 

 

(III).

10. The crosslinkable rubber composition as claimed in any one of claims 5-8, which has the physical properties whereby a crosslinked rubber sheet obtained by molding said rubber composition into a sheet and then subjecting the sheet to hot-air crosslinking has no scratch on the surface in a pencil hardness test using a pencil of HB and has a compression set (CS) of not more than 70% after a heat treatment at 150°

C. for 22 hours.

25. The automobile weatherstrip as claimed in claim 22, which is a glass run product formed from the rubber composition of any one of claims 2 to 12.

7. A crosslinkable rubber composition which comprises:

an ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) having constituent units derived from at least one kind of a vinyl endgroup-containing norbornene compound represented by the following formula (I) or (II), said norbornene compound being the non-conjugated polyene, and

a SiH group-containing compound (B) having at least two SiH groups in one molecule;

wherein n is an integer of 0 to 10, R¹ is a hydrogen atom or an alkyl group of 1 to 10 carbon atoms, and R² is a hydrogen atom or an alkyl group of 1 to 5 carbon atoms;

wherein R³ is a hydrogen atom or an alkyl group of 1 to 10 carbon atoms,

wherein the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) is obtained by copolymerizing ethylene, an α

-olefin and the norbornene compound represented by the formula (I) or (II) using a catalyst containing the following compounds (J) and (K) as main components under the conditions of a polymerization temperature of 30 to 60°

C., a polymerization pressure of 4 to 12 kgf/cm² and a feed rate molar ratio (non-conjugated polyene/ethylene/of the non-conjugated polyene to ethylene ranging from 0.01 to 0.2;

(J) is a soluble vanadium compound represented by VO(OR)_nX<sub>3−

n</sub> wherein R is a hydrocarbon group, X is a halogen atom, and n is 0 or an integer of 1 to 3, or a vanadium compound represented by VX₄ (X is a halogen atom);

(K) is an organoaluminum compound represented by R′

_mAlX′

<sub>3−

m</sub> (R′

is a hydrocarbon group, X′

is a halogen atom, and m is an integer of 1 to

     3).

8. The crosslinkable rubber composition as claimed in claim 7, wherein the ethylene/α

-olefin/non-conjugated polyene random copolymer rubber (A) has an insoluble content of not more than 1% after Soxhlet extraction (solvent;

boiling xylene, extraction time;

3 hours, mesh;

     325).

67. An electric insulating part formed from the crosslinkable rubber composition of any one of clams 1 to 9.