High stretch elastomeric pre-stretched tubes

• US 5,080,942 A
• Filed: 05/23/1990
• Issued: 01/14/1992
• Est. Priority Date: 05/23/1990
• Status: Expired due to Fees

• Current Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Original Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Inventors: Yau, Steven D.
• Primary Examiner(s): Seidleck, James J.
• Assistant Examiner(s): Nold, Charles R.
• Application Number:
  US07/527,525
• Time in Patent Office: 601 Days
• Field of Search: 428/34.9, 428/35.1, 428/36.8, 428/35.8, 174/DIG. 8, 174/73 R, 174/19, 174/135, 174/801, 524/392, 138/177
• US Class Current: 428/34.9
• CPC Class Codes: C08K 3/04 Carbon
• CPC Class Codes: C08K 3/22 of metals
• CPC Class Codes: C08K 3/34 Silicon-containing compounds
• CPC Class Codes: C08K 3/36 Silica
• CPC Class Codes: C08K 5/0025 Crosslinking or vulcanising agents; including accelerators
• CPC Class Codes: C08K 5/10 Esters; Ether-esters
• CPC Class Codes: C08K 5/14 Peroxides
• CPC Class Codes: C08K 5/17 Amines; Quaternary ammonium compounds
• CPC Class Codes: C08K 5/54 Silicon-containing compounds C08K5/0091 takes precedence
• CPC Class Codes: C08L 2205/025 containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
• CPC Class Codes: C08L 2205/03 containing three or more polymers in a blend
• CPC Class Codes: C08L 23/16 Elastomeric ethene-propene or ethene-propene-diene copolymers, e.g. EPR and EPDM rubbers
• CPC Class Codes: C08L 2312/00 Crosslinking
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 9/00 Compositions of homopolymers or copolymers of conjugated diene hydrocarbons
• CPC Class Codes: C08L 91/00 Compositions of oils, fats or waxes; Compositions of derivatives thereof
• CPC Class Codes: H01B 3/441 from alkenes
• CPC Class Codes: H02G 15/068 connected to the cable shield only H02G15/072 takes precedence
• CPC Class Codes: H02G 15/105 connected to the cable shield only H02G15/107 takes precedence
• CPC Class Codes: Y10S 174/08 Shrinkable tubes
• CPC Class Codes: Y10T 428/1328 : Shrinkable or shrunk [e.g., due to heat, solvent, volatile agent, restraint removal, etc.]
• CPC Class Codes: Y10T 428/1386 : Natural or synthetic rubber or rubber-like compound containing

Abstract

Compositions and a process for manufacturing an elastomeric, low modulus pre-stretched tubular article supported by a removable core. The article has a low Shore A hardness value and a low modulus which allows a large expansion ratio and an increased wall thickness.

Claims

1. An article comprising an elastomeric tubular member supported in a stretched condition on an easily removable core, said tubular member comprising:

(a) about 10 to 50 weight percent of an oil-extended ethylene propylene diene monomer rubber,

(b) about 5 to 25 weight percent of an elastomer selected from the group consisting of a nonoil-extended ethylene propylene diene monomer rubber and nonoil-extended ethylene propylene

(c) about 5 to 15 weight percent of an extender,

(d) about 10 to 30 weight percent of a processing oil,

(e) about 2 to 30 weight percent of

silica, and

(f) up to about 30 weight percent of a polymeric plasticizer.

2. The article of claim 1 wherein said extender is aluminum trihydrate.

3. The article of claim 1 further containing up to about 35 weight percent carbon black.

4. The article of claim 1 having a Shore A hardness value below about 33.

5. The article of claim 1 having a 300% stretch modulus at below about 220 pounds per square inch.

6. The article of claim 1 being capable of elongation over about 900%.

7. The article of claim 1 having a tensile strength of over 1000 pounds per square inch.

8. The article of claim 1 further containing about 1 to 5 weight percent of peroxide as a curing.

9. The article of claim 1 having a dielectric strength above about 450 V/mil.

10. The article of claim 1 having an expansion ratio of about 5 to 1.

11. The article of claim 1 having a permanent set of less than about 20%.

12. The article of claim 1 wherein said processing oil is a paraffinic petroleum oil.

13. An article comprising an elastomeric tubular member supported in a stretched condition on an easily removable core, said tubular member comprising:

(a) about 10 to 50 weight percent of an oil-extended ethylene propylene rubber,

(b) about 5 to 25 weight percent of an

elastomer selected from the group consisting of a nonoil-extended ethylene propylene diene monomer rubber and nonoil-extended ethylene propylene rubber,

(c) about 5 to 15 weight percent of an extender,

(d) about 10 to 30 weight percent of a processing oil,

(e) about 2 to 30 weight percent of silica, and

(f) up to about 30 weight percent of a polymeric plasticizer.

14. A process for manufacturing an article comprising an elastomeric tubular member supported in a stretched condition on an easily removable core, said process comprising the steps of:

(a) mixing about 5 to 25 weight percent of an elastomer selected from the group consisting of a nonoil-extended ethylene propylene diene monomer rubber and nonoil-extended ethylene propylene rubber with about 2 to 30 weight percent resin of precipitated silica,

(b) adding about 10 to 50 weight percent of an oil-extended ethylene propylene diene monomer rubber,

(c) adding a sufficient amount of a curative,

(d) heating said mixture to a temperature below the decomposition temperature of said curative,

(e) forming said mixture into an V appropriate shape,

(f) allowing said mixture to cure into a solid composition, and

(g) loading said solid composition on an easily removable core.

15. The process of claim 14 wherein said curative is added in an amount of about 1 to 5 weight percent of a peroxide.