Patent DE2803757C3 successfully refreshed from Google Patents.
US3935249A
Expired / Lapsed
US
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Tar reduction by inorganic halide for reaction of unsaturated anhydride and polybutene
Assignee: Ethyl Corp
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Filing: 1973-05-10
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Granted: 1976-01-27
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Expires: 1993-05-10
Abstract
Abstract Viscous polybutenes of number average molecular weight (M n ) in the range of about 300 to about 3,000 have improved reactivity with intramolecular anhydrides of unsaturated aliphatic dicarboxylic acids when reacted in the presence of rather small amounts, i.e., 5 to 200 ppm, of inorganic halogen preferably chlorine and/or bromine containing compounds. Use of such halogen containing compounds in the addition reaction of polybutene with said unsaturated anhydrides can reduce formation of undesired tarry product resulting from polymerization and/or thermal decomposition of the unsaturated anhydrides.
Inventors
- 👤 Imre Puskas
- 👤 John A. Cengel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:07
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/54; C07C51/567; C08; C08F; C08F8/00; C08F8/46
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
48 words
In the reaction between 300-3,000 M n butene polymer and maleic anhydride to prepare polybutenyl-substituted succinic anhydride, the improvement comprising conducting said reaction at a temperature of from 150° to 300°C in the presence of 5-200 ppm based on said polymer of dry hydrogen chloride or calcium bromide.
Claim 2
Dependent Claim
48 words
In the reaction between 300-3,000 M n butene polymer and maleic anhydride to prepare polybutenyl-substituted succinic anhydride, the improvement comprising conducting said reaction at a temperature of from 150° to 300°C in the presence of 5-200 ppm based on said polymer of dry hydrogen chloride or calcium bromide.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein the inorganic halide is dry hydrogen chloride.
Claim 4
Dependent Claim
12 words
The method of claim 1 wherein the inorganic halide is calcium bromide.
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) | 1979-01-26 | 1979-07-28 | 1980-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-26 | 1983-07-28 | 1984-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-26 | 1987-07-28 | 1988-01-27 | $7700.00 | Window Closed / Lapsed |