US4210474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silicone containing solid propellant
Assignee: National Aeronautics and Space Administration
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Filing: 1978-10-16
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Granted: 1980-07-01
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Expires: 1998-10-16
Abstract
Abstract Addition of a small amount, for example 1% by weight, of a liquid silicone oil to a metal containing solid rocket propellant provides a significant reduction in heat transfer to the inert nozzle walls eliminating metal oxide slag collection and blockage of the nozzle and increases burning rate by about 5 to 10% improving ballistic performance.
Inventors
- 👤 with respect to an invention of Frosch Robert A. Administrator of the National Aeronautics and Space Administration
- 👤 Kumar N. R. Ramohalli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:16
CPC Classifications
C; C06; C06B; C06B23/00; C06B23/007; C06B45/00; C06B45/04; C06B45/06; C06B45/10
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
79 words
A composite solid propellant comprising a continuous phase of 10 to 14% by weight of cured, solid elastomeric polybutadiene binder containing 0.1 to 3% by weight of a polysiloxane liquid oil having a viscosity from 500 to 2,000 centistokes of the formula: ##STR2## where n is an integer and R is an alkyl of 1 to 5 carbon atoms and said binder contains a dispersion of in excess of 85% by weight of combustible solids including metal and oxidizer.
Claim 2
Dependent Claim
79 words
A composite solid propellant comprising a continuous phase of 10 to 14% by weight of cured, solid elastomeric polybutadiene binder containing 0.1 to 3% by weight of a polysiloxane liquid oil having a viscosity from 500 to 2,000 centistokes of the formula: ##STR2## where n is an integer and R is an alkyl of 1 to 5 carbon atoms and said binder contains a dispersion of in excess of 85% by weight of combustible solids including metal and oxidizer.
Claim 3
Dependent Claim
33 words
A propellant according to claim 1 in which the oxidizer is present in an amount from 70-84% by weight and the metal is present in an amount from 2 to 20% by weight.
Claim 4
Dependent Claim
18 words
A propellant according to claim 2 in which the metal is aluminum and the oxidizer is ammonium perchlorate.
Claim 5
Dependent Claim
31 words
A propellant according to claim 3 in which the polybutadiene is selected from carboxy-terminated polybutadienes cured with amines or epoxides, PBAN terpolymers cured with epoxides or hydroxyl-terminated polybutadienes cured with diisocyanates.
Claim 6
Dependent Claim
13 words
A composition according to claim 4 in which the diisocyanate is isophorone diisocyanate.
Claim 7
Dependent Claim
14 words
A composition according to claim 1 in which the silicone oil is a polydimethylsiloxane.
Claim 8
Dependent Claim
17 words
A composition according to claim 6 in which the siloxane has a viscosity of about 1000 cs.
Claim 9
Independent Claim
121 words
A method of reducing aluminum oxide slag deposition in the nozzle of a solid rocket motor containing a high performance solid propellant grain including 10 to 14% by weight of cured, solid elastomeric polybutadiene binder containing a dispersion of in excess of 85% by weight of combustible solids including metal and oxidizer, the improvement comprising the steps of adding to the binder from 0.1% to 3% by weight of a polysiloxane liquid oil having a viscosity from 500 to 2,000 centistokes of the formula: ##STR3## where n is an integer and R is an alkyl of 1 to 5 carbon atoms and said binder contains a dispersion of in excess of 85% by weight of combustible solids including metal and oxidizer.
Claim 10
Independent Claim
121 words
A method of reducing aluminum oxide slag deposition in the nozzle of a solid rocket motor containing a high performance solid propellant grain including 10 to 14% by weight of cured, solid elastomeric polybutadiene binder containing a dispersion of in excess of 85% by weight of combustible solids including metal and oxidizer, the improvement comprising the steps of adding to the binder from 0.1% to 3% by weight of a polysiloxane liquid oil having a viscosity from 500 to 2,000 centistokes of the formula: ##STR3## where n is an integer and R is an alkyl of 1 to 5 carbon atoms and said binder contains a dispersion of in excess of 85% by weight of combustible solids including metal and oxidizer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-07-01 | 1983-12-31 | 1984-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-07-01 | 1987-12-31 | 1988-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-07-01 | 1991-12-31 | 1992-07-01 | $7700.00 | Window Closed / Lapsed |