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US4451640A
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Process for producing aromatic sulfide polymer
Assignee: Kureha Corp
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Filing: 1983-09-16
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Granted: 1984-05-29
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Expires: 2003-09-16
Abstract
Abstract Disclosed herein is a process for producing an aromatic sulfide polymer, comprising the step of reacting elementary sulfur, a polyhalogen-substituted aromatic compound, an aldehyde or a condensate thereof and a caustic alkali in an organic solvent.
Inventors
- 👤 Zenya Shiiki
- 👤 Yukichika Kawakami
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:27
CPC Classifications
C; C08; C08G; C08G75/00; C08G75/02; C08G75/0204; C08G75/0236; C08G75/0209; C08G75/0231; C08G75/025; C08G75/0263; C08G75/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
64 words
A process for producing an aromatic sulfide polymer, comprising the step of reacting one gram-equivalent of elementary sulfur, 0.7 to 1.3 gram-equivalents of a polyhalogen-substituted aromatic compound, 0.6 to 1.4 gram-equivalents of an aldehyde or a condensate thereof and 1.2 to 2.5 gram-equivalents of a caustic alkali in 0.02 to 5 liters of an organic solvent at a temperature of 100° to 300° C.
Claim 2
Dependent Claim
64 words
A process for producing an aromatic sulfide polymer, comprising the step of reacting one gram-equivalent of elementary sulfur, 0.7 to 1.3 gram-equivalents of a polyhalogen-substituted aromatic compound, 0.6 to 1.4 gram-equivalents of an aldehyde or a condensate thereof and 1.2 to 2.5 gram-equivalents of a caustic alkali in 0.02 to 5 liters of an organic solvent at a temperature of 100° to 300° C.
Claim 3
Dependent Claim
48 words
A process according to claim 1, wherein one gram-equivalent of elementary sulfur, 0.8 to 1.2 gram-equivalents of said polyhalogen-substituted aromatic compound, 1.4 to 1.7 gram-equivalents of said caustic alkali are reacted in 0.02 to 5 liters of said organic solvent at a temperature of 150° to 280° C.
Claim 4
Dependent Claim
20 words
A process according to claim 1 or 2, wherein said elementary sulfur is rhombic sulfur, monoclinic sulfur or amorphous sulfur.
Claim 5
Dependent Claim
38 words
A process according to claim 1, wherein said polyhalogen-substituted aromatic compound is a member selected from the group consisting of dichlorobenzenes, dibromobenzenes, trichlorobenzenes, 1-methoxy-2,5-dichlorobenzene, 2,5-dichlorotoluene, 1,4-dichloronaphthalene, 4,4'-dichlorobiphenyl, 4,4'-dichlorodiphenyl ether, 3,5-dichlorobenzoic acid, 3,3'-dichlorodiphenyl sulfone, 3,3'-dichlorodiphenyl sulfoxide and 3,3'-dichlorodiphenyl sulfide.
Claim 6
Dependent Claim
33 words
A process according to claim 1, wherein said aldehyde or said condensate thereof is a member selected from the group consisting of formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, benzaldehyde, paraformaldehyde, trioxane, polyoxymethylenes, paraacetaldehyde and metaacetaldehyde.
Claim 7
Dependent Claim
28 words
A process according to claim 1, wherein said organic solvent is a member selected from the group consisting of hexamethyl phosphoric triamide, N-methylpyrrolidone, tetramethyl-urea, dimethylacetamide and tetramethylene sulfoxide.
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) | 1987-05-29 | 1987-11-28 | 1988-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-29 | 1991-11-28 | 1992-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-29 | 1995-11-28 | 1996-05-29 | $7700.00 | Window Closed / Lapsed |