US3607843A
Expired / Lapsed
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Process for making poly (phenylene sulfide) polymers of increased molecular weight
Assignee: Phillips Petroleum Co
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Filing: 1969-05-16
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Granted: 1971-09-21
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Expires: 1989-05-16
Abstract
Abstract The inherent viscosity of poly(phenylene sulfide) polymers is substantially increased and the range narrowed by recycling to the reactor as one of the reaction ingredients previously produced poly(phenylene sulfide) polymer.
Inventors
- 👤 Fernando C Vidaurri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:00
CPC Classifications
C; C08; C08G; C08G75/00; C08G75/02; C08G75/0204; C08G75/0286; C08G75/025; C08G75/0254; C08G75/0295; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/582
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
52 words
The process of claim 1 wherein said polyhalogenated compound is a dihalo-substituted ring compound wherein the halogen atoms thereof are selected from at least one of fluorine, chlorine, bromine, and iodine, and are attached to ring carbon atoms; and said alkali metal sulfide is a sulfide of lithium, sodium, potassium, or rubidium.
Claim 2
Dependent Claim
48 words
The process of claim 2 wherein said dihalo-substituted ring compound is selected from p-dichlorobenzene, 4,4''-dibromobiphenyl, 2,5-dibromothiophene, 4,4''-bis-p-bromophenyl ether, and 2,5-dichlorobenzene-sulfonic acid; and the said polar organic compound is selected from at least one of hexamethyl phosphoramide, tetramethylurea, N,N''-ethylene dipyrrolidone, N-methyl-2-pyrrolidone, pyrrolidone, caprolactam, N-ethylcaprolactam, sulfolane, dimethylacetamide, and mixtures thereof.
Claim 3
Dependent Claim
53 words
The process of claim 1 wherein in said step (a) said dihalo-substituted ring compound is p-dichlorobenzene, and said alkali metal sulfide is sodium sulfide, and each of which is employed at from about 0.05 to 0.5 mole per each mole of said polar organic compound, and wherein said polar organic compound is N-methyl-2-pyrrolidone.
Claim 4
Dependent Claim
26 words
The process of claim 3 wherein is used in step (a) from about 5 to about 33 weight percent of lower inherent viscosity recycle poly(phenylene sulfide).
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 |