US3865897A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of blending polyolefins and polydiorganosiloxane gums and blends thereof
Assignee: Dow Silicones Corp
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Filing: 1973-08-03
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Granted: 1975-02-11
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Expires: 1993-08-03
Abstract
Abstract Mechanically mixing 7 to 75 weight percent of a polydiorganosiloxane gum having 1.5 to 17 mol percent vinyl or allyl bearing siloxane units with 25 to 93 weight percent of a low density polyethylene, a high density polyethylene, polymethylpentene, polypropylene or a copolymer of tetrafluorethylene and ethylene at a shear rate greater than 10 sec 1 for a period of time suitable to obtain a viscosity within 60 percent of the maximum viscosity obtainable at mixing conditions where the temperature is from 175* to 300*C. for low density polyethylene, from 200* to 320*C. for high density polyethylene, from 225* to 300*C. for polymethylpentene, from 215* to 300*C. for polypropylene and from 275* to 350*C. for the copolymer of tetrafluorethylene and ethylene produces a blend of lower modulus suitable for electrical insulation.
Inventors
- 👤 James R Falender
- 👤 Sarah E Lindsey
- 👤 John C Saam
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:01
CPC Classifications
C; C08; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/06; C08L83/00; C08L83/04; C08G; C08G77/00; C08G77/04; C08G77/20; C08G77/42; C08G77/70; C08L2207/00; C08L2207/06; C08L2207/066
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
245 words
A METHOD OF BLENDING A POLYOLEFIN AND POLYDIORGANOSILOXANE GUM COMPRISING MECHANICALLY MIXING A POLYDIORGANOSILOXANE GUM AND A POLYOLEFIN SELECTED FROM THE GROUP CONSISTING A LOW DENSITY POLYETHYLENE, HIGH DENSITY POLYETHYLENE, POLYMETHYLPENTENE, POLYPROPYLENE AND A COPOLYMER CONSISTING OF TETRAFLUOROETHYLENE REPEATING UNITS AND ETHYLENE REPEATING UNITS, AT A SHEAR RATE GREATER THAN 10 SEC-1 FOR A PERIOD OF TIMES SUITABLE TO OBTAIN A VISCOSITY WITHIN 60 PERCENT OF THE MAXIMUM VISCOSITY OBTAINABLE AT MIXING CONDITIONS, AND AT A TEMPERATURE WITHIN A RANGE FOR EACH POLYOLEFIN OF FROM 1975* TO 300*C. FOR LOW DENSITY POLYETHYLENE, FROM 200* TO 320C. FOR HIGH DENSITY POLYETHYLENE FROM 225* TO 300*C. FOR POLYMETHYLPENTENE, FROM 215* TO 300*C. FOR POLYPROPYLENE AND FROM 275* TO 350*C. FOR COPOLOPMERS OF TETRAFLUOROETHYLENE REPEATING UNITS AND ETHYLENE REPEATING UNITS AND THEREAFTER RECOVERING A PROCESSABLE STABLE, HOMOGENEOUS BLEND, SAID POLYDIORGANOSILOXANE GUM BEING PRESENT IN AN AMOUNT OF FROM 7 TO 75 WEIGHT PERCENT AND SAID POLYOLEFIN BEING PRESENT IN AN AMOUNT OF FROM 25 TO 93 WEIGHT PERCENT WHEREIN THE COMBINED WEIGHT OF THE POLYDIORGANOSILOZANE GUM AND POLYOLEFIN IS 100 WEIGHT PERCENT SAID POLYDIORGANOSILOXANE GUM BEING TOLUENT SOLUBLE GUM HAVING A WILLIAMS PLASTICITY GREATER THAN 0.020 INCH, WITH A RATIO OF ORGANICS GROUPS PER SILICON ATOM OF ABOUT TWO WHEREIN THE ORGANIC GROUPS ARE SELECTED FROM METHYL, PHENYL,VINYL AND ALLYL WITH FROM 1.5 TO 17 MOL PERCENT OF THE SILOXANE UNITS HAVING VINYL OR ALLYL GROUPS AND NO MORE THAN 50 PERCENT OF THE ORGANIC GROUPS BEING PHENYL.
Claim 2
Independent Claim
245 words
A METHOD OF BLENDING A POLYOLEFIN AND POLYDIORGANOSILOXANE GUM COMPRISING MECHANICALLY MIXING A POLYDIORGANOSILOXANE GUM AND A POLYOLEFIN SELECTED FROM THE GROUP CONSISTING A LOW DENSITY POLYETHYLENE, HIGH DENSITY POLYETHYLENE, POLYMETHYLPENTENE, POLYPROPYLENE AND A COPOLYMER CONSISTING OF TETRAFLUOROETHYLENE REPEATING UNITS AND ETHYLENE REPEATING UNITS, AT A SHEAR RATE GREATER THAN 10 SEC-1 FOR A PERIOD OF TIMES SUITABLE TO OBTAIN A VISCOSITY WITHIN 60 PERCENT OF THE MAXIMUM VISCOSITY OBTAINABLE AT MIXING CONDITIONS, AND AT A TEMPERATURE WITHIN A RANGE FOR EACH POLYOLEFIN OF FROM 1975* TO 300*C. FOR LOW DENSITY POLYETHYLENE, FROM 200* TO 320C. FOR HIGH DENSITY POLYETHYLENE FROM 225* TO 300*C. FOR POLYMETHYLPENTENE, FROM 215* TO 300*C. FOR POLYPROPYLENE AND FROM 275* TO 350*C. FOR COPOLOPMERS OF TETRAFLUOROETHYLENE REPEATING UNITS AND ETHYLENE REPEATING UNITS AND THEREAFTER RECOVERING A PROCESSABLE STABLE, HOMOGENEOUS BLEND, SAID POLYDIORGANOSILOXANE GUM BEING PRESENT IN AN AMOUNT OF FROM 7 TO 75 WEIGHT PERCENT AND SAID POLYOLEFIN BEING PRESENT IN AN AMOUNT OF FROM 25 TO 93 WEIGHT PERCENT WHEREIN THE COMBINED WEIGHT OF THE POLYDIORGANOSILOZANE GUM AND POLYOLEFIN IS 100 WEIGHT PERCENT SAID POLYDIORGANOSILOXANE GUM BEING TOLUENT SOLUBLE GUM HAVING A WILLIAMS PLASTICITY GREATER THAN 0.020 INCH, WITH A RATIO OF ORGANICS GROUPS PER SILICON ATOM OF ABOUT TWO WHEREIN THE ORGANIC GROUPS ARE SELECTED FROM METHYL, PHENYL,VINYL AND ALLYL WITH FROM 1.5 TO 17 MOL PERCENT OF THE SILOXANE UNITS HAVING VINYL OR ALLYL GROUPS AND NO MORE THAN 50 PERCENT OF THE ORGANIC GROUPS BEING PHENYL.
Claim 3
Dependent Claim
12 words
The processable, stable, homogeneous blend prepared by the method of claim 1.
Claim 4
Dependent Claim
35 words
The method in accordance with claim 1 in which the polyolefin is low density polyethylene, the temperature is from 175* to 300*C. and the amount of polydiorganosiloxane gum is from 10 to 75 weight percent.
Claim 5
Dependent Claim
35 words
The method in accordance with claim 1 in which the polyolefin is high density polyethylene, the temperature is from 200* to 320*C. and the amount of polydiorganosiloxane gum is from 7 to 50 weight percent.
Claim 6
Dependent Claim
33 words
The method in accordance with claim 1 in which the polyolefin is polymethylpentene, the temperature is from 225* to 300*C. and the amount of polydiorganosiloxane gum is from 10 to 25 weight percent.
Claim 7
Dependent Claim
32 words
The method in accordance with claim 1 in which the polyolefin is polypropylene, the temperature is from 215* to 300*C. and the amount of polydiorganosiloxane is from 10 to 60 weight percent.
Claim 8
Dependent Claim
41 words
The method in accordance with claim 1 in which the polyolefin is a copolymer of tetrafluoroethylene repeating units and ethylene repeating units, the temperature is from 275* to 350*C. and the amount of polydiorganosiloxane is from 10 to 20 weight percent.
Claim 9
Dependent Claim
39 words
The method in accordance with claim 1 in which the polydiorganosiloxane is present in an amount of 55 to 75 weight percent and said mechanical mixing being done in the presence of at least a small amount of oxygen.
Claim 10
Dependent Claim
156 words
A processable blend prepared by the method of claim 1 consisting essentially of 25 to 93 weight percent polyethylene and 7 to 75 weight percent polydiorganosiloxane gum where the combined weight of the polyethylene and the polydiorganosiloxane gum is 100 weight percent, wherein at least some of the polydiorganosiloxane gum and the polyethylene are bonded to each other forming a graft copolymer, there being present at least 50 weight percent of the total blend of material which is insoluble in refluxing xylene, said polydiorganosiloxane gum before becoming a component of said blend being soluble in toluene, having a Williams plasticity greater than 0.020 inch, having a ratio of organic groups per silicon atom of about two, wherein the organic groups are selected from methyl, phenyl, vinyl and allyl with from 1.5 to 17 mol percent of the siloxane units having vinyl or allyl groups and no more than 50 percent of the organic groups being phenyl.
References Cited (Backward Citations)
US2930083A
Cited
US3798185A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-10 | 1978-08-12 | 1979-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-10 | 1982-08-12 | 1983-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-10 | 1986-08-12 | 1987-02-11 | $7700.00 | Window Closed / Lapsed |