US3607810A
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Aqueous alkaline solutions of polyhydrazides
Assignee: Glanzstoff AG
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Filing: 1968-05-07
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Granted: 1971-09-21
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Expires: 1988-05-07
Abstract
Abstract As a composition of matter, a dilute aqueous alkaline solution in which there is dissolved a polyhydrazide characterized by recurring polymeric units of the formula -NH-NH-CO-R-CO-NH-NH-COR''-CO-n (I) in which R and R'' represent divalent aromatic or heterocyclic radicals such a phenylene, naphthalene or diphenylether and n is a large integer. This alkaline polymer solution can be used to form shaped products which in turn can be converted by heating into thermally-stable and insoluble polyoxadiazoles.
Inventors
- 👤 Albert Schopf
- 👤 Gerhard Meyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:42
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/08
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
19 words
A composition as claimed in claim 1 wherein R represents phenylene or naphthalene and R'' represents phenylene or diphenylether.
Claim 2
Dependent Claim
24 words
A composition as claimed in claim 2 wherein the aqueous solution has an alkali metal hydroxide concentration of about 0.2 to 0.9 mol percent.
Claim 3
Dependent Claim
15 words
A composition as claimed in claim 3 wherein the alkali metal hydroxide is potassium hydroxide.
Claim 4
Dependent Claim
15 words
A composition as claimed in claim 3 wherein the alkali metal hydroxide is sodium hydroxide.
Claim 5
Dependent Claim
42 words
A composition as claimed in claim 3 wherein R of Formula I represents 2,6-naphthalene and R'' of Formula I represents 1,3-phenylene, and the polyhydrazide is dissolved in an aqueous KOH solution having a KOH concentration of about 0.2 to 0.6 mol percent.
Claim 6
Dependent Claim
42 words
A composition as claimed in claim 3 wherein R of Formula I represents 2,6-naphthalene and R'' of Formula I represents 1,3-phenylene, and the polyhydrazide is dissolved in an aqueous NaOH solution having a NaOH concentration of about 0.2 to 0.6 mol percent.
Claim 7
Dependent Claim
42 words
A composition as claimed in claim 3 wherein R of Formula I represents 1,3-phenylene and R'' of Formula I represents p,p''-diphenylether, and the polyhydrazide is dissolved in an aqueous KOH solution having a KOH concentration of about 0.2 to 0.4 mol percent.
Claim 8
Dependent Claim
39 words
A composition as claimed in claim 3 wherein each of R and R'' in Formula I represent 1,3-phenylene, and the polyhydrazide is dissolved in an aqueous KOH solution having a KOH concentration of about 0.3 to 0.85 mol percent.
Claim 9
Dependent Claim
42 words
A composition as claimed in claim 3 wherein R in Formula I represents 1,4-phenylene and R'' in Formula I represents 1,3-phenylene, and the polyhydrazide is dissolved in an aqueous KOH solution having a KOH concentration of about 0.2 to 0.45 mol percent.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-20 | 1975-03-22 | 1975-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-20 | 1979-03-22 | 1979-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-20 | 1983-03-22 | 1983-09-21 | $7700.00 | Window Closed / Lapsed |