Patent US3669924A successfully refreshed from Google Patents.
US3669924A
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Stabilized polyvinyl nitrate and process
Assignee: Rheinmetall Air Defence AG
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Filing: 1969-09-11
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Granted: 1972-06-13
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Expires: 1989-09-11
Abstract
Abstract A novel stabilized polyvinylnitrate and a process for the production thereof including the precipitation of the compound from organic solutions containing same.
Inventors
- 👤 Eduard Daume
- 👤 Jurg Breitenmoser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:45
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/02; C08J3/09; C06; C06B; C06B45/00; C06B45/04; C06B45/06; C06B45/10; C06B45/105; C08J2329/00; C08J2329/02; C08J2329/04
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
27 words
A process as in claim 1 in which step (b) is carried out by using an aqueous neutralizing solution of an alkali metal hydroxide, bicarbonate or carbonate.
Claim 2
Dependent Claim
21 words
A process as in claim 1 in which step (b) is carried out by using an aqueous neutralizing solution of NaHCO3.
Claim 3
Dependent Claim
31 words
A process as in claim 1 in which in step (a) a solvent is used selected from the group comprising an ester and a ketone at most partially miscible with water.
Claim 4
Dependent Claim
18 words
A process as in claim 1 in which in step (a) ethyl acetate is used as a solvent.
Claim 5
Dependent Claim
26 words
A process as in claim 1 further comprising the step of diluting the solutions of step (b) with the same solvent as used in step (a).
Claim 6
Dependent Claim
60 words
A process as in claim 1 in which a solution of about 20 parts by weight of crude polyvinylnitrate in about 80 parts by weight of ethyl acetate is prepared iN step (a), and further comprising the dilution of the neutralized solution of step (b) with ethyl acetate to a concentration of about 10 percent by weight of polyvinyl nitrate.
Claim 7
Dependent Claim
23 words
A process as in claim 1, further comprising the step of adding to said solution after step (c) 2-nitrodiphenylamine as a stabilizing agent.
Claim 8
Dependent Claim
42 words
A process as in claim 1 in which the precipitating bath of step (d) is selected from the group comprising pure water and an aqueous medium containing at least one additive of the group consisting of electrolytes, protection colloids and pH regulators.
Claim 9
Dependent Claim
41 words
A process as in claim 1 in which an aqueous precipitating bath is used in step (d) which has been previously saturated with the organic solvent of step (a) in the range between normal room temperature and the azeotropic boiling point.
Claim 10
Dependent Claim
25 words
A process as in claim 1, further comprising the step of vigorously agitating the precipitating bath of step (d) during and after the precipitating period.
Claim 11
Dependent Claim
37 words
A process as in claim 1, further comprising the step of continuing stripping off the solvent in step (d) after the feed of said polyvinylnitrate solution has been stopped until said precipitating bath is substantially solvent free.
References Cited (Backward Citations)
US2118487A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |