US4038115A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite modified double-base propellant with filler bonding agent
Assignee: Hercules LLC
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Filing: 1969-10-07
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Granted: 1977-07-26
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Expires: 1989-10-07
Abstract
Abstract Mechanical properties of composite modified double-base propellant are improved by coating fillers for the propellant with a crosslinked, binder insoluble coating having reactive surface isocyanate groups. The reactive isocyanate groups become chemically bound to the nitrocellulose binder of the propellant during propellant cure. Failure of the propellant at the binder-filler interface under conditions of stress is substantially reduced.
Inventors
- 👤 Henry C. Dehm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:19
CPC Classifications
C; C06; C06B; C06B25/00; C06B25/18; C06B25/24; C06B25/26; C06B21/00; C06B21/0083; C06B45/00; C06B45/18; C06B45/20; C06B45/22
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
95 words
A process for providing fillers for composite modified double-base propellant with a crosslinked, binder-insoluble coating having reactive surface-NCO groups, said process comprising, a. coating at least one filler for a composite modified double-base propellant and selected from the group consisting of inorganic oxidizer salts, organic oxidizers and metal fuels with a polyol, b. reacting the polyol coated filler with an organic isocyanate having an NCO functionality of at least three in the presence of a catalyst, and c. recovering a filler for composite modified double-base propellant having a crosslinked, binder-insoluble coating having reactive surface-NCO groups.
Claim 2
Dependent Claim
95 words
A process for providing fillers for composite modified double-base propellant with a crosslinked, binder-insoluble coating having reactive surface-NCO groups, said process comprising, a. coating at least one filler for a composite modified double-base propellant and selected from the group consisting of inorganic oxidizer salts, organic oxidizers and metal fuels with a polyol, b. reacting the polyol coated filler with an organic isocyanate having an NCO functionality of at least three in the presence of a catalyst, and c. recovering a filler for composite modified double-base propellant having a crosslinked, binder-insoluble coating having reactive surface-NCO groups.
Claim 3
Dependent Claim
23 words
The process of claim 1 in which the polyol has at least one hydroxyl group for every four carbon atoms of the polyol.
Claim 4
Dependent Claim
29 words
The process of claim 2 in which the ratio of hydroxyl functionality of the polyol to NCO functionality of the organic isocyanate is from about 1/2 to about 1/20.
Claim 5
Dependent Claim
33 words
The process of claim 3 in which the amount of polyol employed in the polyol coating step is from about 0.05 to about 2.5% by weight, based on the weight of the filler.
Claim 6
Dependent Claim
115 words
A process for providing fillers for composite modified double-base propellant with a crosslinked, binder-insoluble coating having reactive surface-NCO groups, said process comprising a. mixing a filler selected from the group consisting of cyclotetramethylene tetranitramine (HMX), cyclotrimethylene trinitramine (RDX), and mixtures thereof, and a polyol dissolved in an aprotic solvent, said aprotic solvent being a non-solvent for the filler, b. removing the polyol solvent from the admixture whereby the polyol is deposited on the surface of the filler, c. reacting the polyol coated filler with an organic isocyanate having an NCO functionality of at least three in the presence of a catalyst, and d. recovering the filler having a crosslinked, binder-insoluble coating having reactive surface-NCO groups.
Claim 7
Dependent Claim
115 words
A process for providing fillers for composite modified double-base propellant with a crosslinked, binder-insoluble coating having reactive surface-NCO groups, said process comprising a. mixing a filler selected from the group consisting of cyclotetramethylene tetranitramine (HMX), cyclotrimethylene trinitramine (RDX), and mixtures thereof, and a polyol dissolved in an aprotic solvent, said aprotic solvent being a non-solvent for the filler, b. removing the polyol solvent from the admixture whereby the polyol is deposited on the surface of the filler, c. reacting the polyol coated filler with an organic isocyanate having an NCO functionality of at least three in the presence of a catalyst, and d. recovering the filler having a crosslinked, binder-insoluble coating having reactive surface-NCO groups.
Claim 8
Dependent Claim
111 words
A process for providing filler for composite modified double-base propellant with a crosslinked, binder-insoluble coating having reactive surface-NCO groups, said process comprising, a. admixing a filler selected from the group consisting of ammonium nitrate, ammonium perchlorate and mixtures thereof and a polyol which is an aminoalcohol, said polyol being dissolved in an aprotic solvent which is a non-solvent for the filler, until substantially complete reaction between the filler and the amino-alcohol has taken place, b. reacting the polyol coated filler with an isocyanate having an NCO functionality of at least three in the presence of a catalyst, and c. recovering a filler having a crosslinked, binder-insoluble coating having reactive surface-NCO groups.
Claim 9
Dependent Claim
111 words
A process for providing filler for composite modified double-base propellant with a crosslinked, binder-insoluble coating having reactive surface-NCO groups, said process comprising, a. admixing a filler selected from the group consisting of ammonium nitrate, ammonium perchlorate and mixtures thereof and a polyol which is an aminoalcohol, said polyol being dissolved in an aprotic solvent which is a non-solvent for the filler, until substantially complete reaction between the filler and the amino-alcohol has taken place, b. reacting the polyol coated filler with an isocyanate having an NCO functionality of at least three in the presence of a catalyst, and c. recovering a filler having a crosslinked, binder-insoluble coating having reactive surface-NCO groups.
Claim 10
Dependent Claim
71 words
In the process of preparing composite modified double-base propellant by slurry casting, the improvement whereby dewetting of filler particles from the binder under conditions of stress is reduced said improvement comprising admixing with the uncured propellant ingredients at least one filler selected from the group consisting of inorganic oxidizer salts, organic oxidizers and metal fluids, said filler having a crosslinked, binder-insoluble coating having reactive surface-NCO groups, and curing the resulting propellant.
Claim 11
Dependent Claim
71 words
In the process of preparing composite modified double-base propellant by slurry casting, the improvement whereby dewetting of filler particles from the binder under conditions of stress is reduced said improvement comprising admixing with the uncured propellant ingredients at least one filler selected from the group consisting of inorganic oxidizer salts, organic oxidizers and metal fluids, said filler having a crosslinked, binder-insoluble coating having reactive surface-NCO groups, and curing the resulting propellant.
Claim 12
Dependent Claim
26 words
The process of claim 7 in which the filler having a crosslinked, binder-insoluble coating having reactive surface-NCO groups is prepared by the process of claim 1.
Claim 13
Dependent Claim
28 words
The process of claim 7 in which the filler having a crosslinked, binder-insoluble coating having reactive surface-NCO groups is a filler coated by the process of claim 5.
Claim 14
Dependent Claim
28 words
The process of claim 7 in which the filler having a crosslinked, binder-insoluble coating having reactive surface-NCO groups is a filler coated by the process of claim 6.
Claim 15
Dependent Claim
15 words
The cured composite modified double-base propellant prepared in accordance with the process of claim 7.
Claim 16
Dependent Claim
12 words
The cured composite modified double-base propellant prepared in accordance with claim 8.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-25 | 1981-01-24 | 1981-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-25 | 1985-01-24 | 1985-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-25 | 1989-01-24 | 1989-07-26 | $7700.00 | Window Closed / Lapsed |