Patent US3953401A successfully refreshed from Google Patents.
US3953401A
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US
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Process for separating aromatic polymers from solution
Assignee: Inventa AG fuer Forschung und Patentverwertung
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Filing: 1974-01-22
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Granted: 1976-04-27
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Expires: 1994-01-22
Abstract
Abstract A process for separating aromatic polymers from solutions containing them which comprises spraying the polymer solution, under pressure, onto the surface of a moving precipitation medium of the general formula ROH in which R is hydrogen or a lower alkyl group.
Inventors
- 👤 Rudolf Gabler
- 👤 Josef Studinka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 14:31
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/12; C08G; C08G75/00; C08G75/20; C08G75/23; C08J2381/00; C08J2381/06
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
153 words
A process for isolating a high molecular weight aromatic polymer in the form of a fine, uniform powder, said polymer being easily freed of residual salts and solvent, which comprises a. dissolving in an aprotic solvent a polymer having the repeating structure (I): ##SPC13## in which the linking bonds on any particular benzene ring are positioned meta or para to each other, in which x, y and z, each being the same or different, consist of the radicals --O--, --S--, --SO 2 -- --CO--, --CONH--, --N=N--, --C(CH 3 ) 2 --, --(CH 2 ) n -- where n is 1 or 2, or a direct bond between the benzene rings; and b. spraying the polymer solution onto the surface of a moving precipitation medium having the formula ROH in which R is a hydrogen or an alkyl group having 1 to 4 carbon atoms, thereby precipitating said polymer in a fine, uniform powder.
Claim 2
Dependent Claim
153 words
A process for isolating a high molecular weight aromatic polymer in the form of a fine, uniform powder, said polymer being easily freed of residual salts and solvent, which comprises a. dissolving in an aprotic solvent a polymer having the repeating structure (I): ##SPC13## in which the linking bonds on any particular benzene ring are positioned meta or para to each other, in which x, y and z, each being the same or different, consist of the radicals --O--, --S--, --SO 2 -- --CO--, --CONH--, --N=N--, --C(CH 3 ) 2 --, --(CH 2 ) n -- where n is 1 or 2, or a direct bond between the benzene rings; and b. spraying the polymer solution onto the surface of a moving precipitation medium having the formula ROH in which R is a hydrogen or an alkyl group having 1 to 4 carbon atoms, thereby precipitating said polymer in a fine, uniform powder.
Claim 3
Dependent Claim
17 words
The process of claim 1 in which the aprotic solvent is dimethylsulfoxide, dimethylformamide, sulfolane, dimethylacetamide, or tetramethylurea.
Claim 4
Dependent Claim
15 words
The process of claim 1 in which the aromatic polymer has the repeating structure ##SPC14##
Claim 5
Dependent Claim
15 words
The process of claim 1 in which the aromatic polymer has the repeating structure ##SPC15##
Claim 6
Dependent Claim
15 words
The process of claim 1 in which the aromatic polymer has the repeating structure ##SPC16##
Claim 7
Dependent Claim
15 words
The process of claim 1 in which the aromatic polymer has the repeating structure ##SPC17##
Claim 8
Dependent Claim
15 words
The process of claim 1 in which the aromatic polymer has the repeating structure ##SPC18##
Claim 9
Dependent Claim
26 words
The process of claim 1 in which the aromatic polymer is a copolymer with irregular structural elements, said copolymer being prepared from 4-mercapto-phenol and 4,4'-dichlorodiphenyl sulfone.
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) | 1979-04-27 | 1979-10-27 | 1980-04-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-27 | 1983-10-27 | 1984-04-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-27 | 1987-10-27 | 1988-04-27 | $7700.00 | Window Closed / Lapsed |