US4446090A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High viscosity silicone blending process
Assignee: General Electric Co
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Filing: 1983-10-03
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Granted: 1984-05-01
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Expires: 2003-10-03
Abstract
Abstract A method of continuously producing blends of thermoplastic polymers and high viscosity silicone fluids is provided by injecting the silicone fluid into an extruder where the thermoplastic polymers are molten. The dispersion of the silicone fluid can be controlled by adjusting the blending temperature and blends having superior engineering properties and flame retardance produced.
Inventors
- 👤 Eric M. Lovgren
- 👤 Joseph C. Golba, Jr.
- 👤 Randall A. Reed
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:46
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/54; C08J; C08J3/00; C08J3/005
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
67 words
A method of continuously producing a thermoplastic/silicone fluid blend comprising (a) melting a solid thermoplastic composition comprising one or more thermoplastic polymers within an extruder; (b) injecting a high viscosity silicone fluid having a viscosity of at least 90,000 centipoise at ambient temperature into the molten thermoplastic composition within the extruder; and (c) blending said molten thermoplastic composition with said high viscosity silicone fluid within the extruder.
Claim 2
Independent Claim
67 words
A method of continuously producing a thermoplastic/silicone fluid blend comprising (a) melting a solid thermoplastic composition comprising one or more thermoplastic polymers within an extruder; (b) injecting a high viscosity silicone fluid having a viscosity of at least 90,000 centipoise at ambient temperature into the molten thermoplastic composition within the extruder; and (c) blending said molten thermoplastic composition with said high viscosity silicone fluid within the extruder.
Claim 3
Dependent Claim
28 words
A method as in claim 1 comprising the additional step of controlling the temperature at which the molten thermoplastic composition is blended with the high viscosity silicone fluid.
Claim 4
Dependent Claim
37 words
A method as in claim 2 wherein the temperature at which said molten thermoplastic composition is blended with said high viscosity silicone fluid is controlled by adjusting the temperature of said molten thermoplastic composition prior to blending.
Claim 5
Dependent Claim
38 words
A method as in claim 1 wherein the high viscosity silicone fluid is injected into the extruder at a point between about 1/3 and 1/2 the extruder length downstream from the point where said thermoplastic composition is fed.
Claim 6
Dependent Claim
48 words
A method as in claim 1 wherein said thermoplastic composition is comprised essentially of one or more thermoplastic polymers selected from the group consisting of polycarbonates, low density polyethylenes, high density polyethylenes, polypropylene, polyphenylene ethers, poly(alkylene terephthalate)s, polystyrenes, polyesters, polyamides, polyimides, polyurethanes, ter-polymers of acrylonitriles, butadiene, and styrene.
Claim 7
Dependent Claim
66 words
A method as in claim 5 wherein said thermoplastic composition contains 50-97% thermoplastic polymers, 0-20% fillers selected from the group consisting of talc, clay, fumed silica, calcium carbonate, and wallastonite; 0-40% flame retardants selected from the group consisting of magnesium stearate, calcium stearate, barium stearate and decabromodiphenyloxide and 0-40% cross linking agents selected from the group consisting of dicumyl peroxide wherein all percentages are by weight.
Claim 8
Dependent Claim
24 words
A method as in claim 6 comprising the additional step of preblending the thermoplastic composition prior to injection of the high viscosity silicone fluid.
Claim 9
Dependent Claim
18 words
A method as in claim 1 wherein said high viscosity silicone fluid is comprised of about 20-100% polydimethylsiloxane.
Claim 10
Dependent Claim
38 words
A process as in claim 8 wherein said high viscosity silicone fluid contains about 2-50% MQ silicone resin wherein the ratio of M units to Q units provides a value within the range of about 0.3 to 4.0.
Claim 11
Dependent Claim
15 words
A method as in claim 2 wherein the thermoplastic composition is comprised substantially of polypropylene.
Claim 12
Dependent Claim
23 words
A method as in claim 10 wherein the temperature during blending is maintained at a value in the range of about 200°-275° C.
Claim 13
Dependent Claim
22 words
A method as in claim 11 wherein the blending temperature is maintained at a value in the range of about 210°-240° C.
Claim 14
Dependent Claim
35 words
A method as in claim 1 where the molten thermoplastic composition is comprised of about 80% polypropylene, about 7% talc, about 23% decabromodiphenyl oxide and about 10% magnesium stearate, wherein all percentages are by weight.
Claim 15
Dependent Claim
41 words
A thermoplastic silicone fluid blend produced in accordance with the process in claim 4, said blend comprising: (a) 50-97 wt. percent of polypropylene; (b) 1-40 wt. percent polydimethylsiloxane; (c) 1-20 wt. percent magnesium stearate; and (d) 1-20 wt. percent MQ resin.
References Cited (Backward Citations)
US2884388A
Cited
US2999835A
Cited
US3087908A
Cited
US3795646A
Cited
US3737479A
Cited
US3728294A
Cited
US3865897A
Cited
JPS5078648A
Cited
US3929708A
Cited
US4164603A
Cited
US4135870A
Cited
US4263416A
Cited
US4273691A
Cited
US4299256A
Cited
US4387176A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-05-01 | 1987-10-31 | 1988-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-01 | 1991-10-31 | 1992-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-01 | 1995-10-31 | 1996-05-01 | $7700.00 | Window Closed / Lapsed |