Patent US3853960A successfully refreshed from Google Patents.
US3853960A
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Process for the manufacture of penthaerythritol tetracarbamate
Assignee: Proctor Chemical Co Inc
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Filing: 1972-05-09
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Granted: 1974-12-10
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Expires: 1992-05-09
Abstract
Abstract Pentaerythritol tetracarbamate, as a new compound, is prepared by transesterification of pentaerythritol with a carbamate ester of a low boiling alcohol, e.g., C1-C4 alkanols. The PETC is recovered by filtration from the remainder of the reaction mass which is liquid at temperatures above 90*C. in which the PETC is insoluble.
Inventors
- 👤 M Crowther
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:37
CPC Classifications
C; C07; C07C; C07C271/00; C07C271/06
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
141 words
A PROCESS FOR THE MANUFACTURE OF PENTAERYTHRITOL TETRACARBAMATE WHICH COMPRISES: A. PROVIDING A REACTION MIXTURE CONSISTING ESSENTIALLY OF PENTAERYTHRITOL, 6 TO 10 MOLS OF A CARBAMATE ESTER OF AN ALKANOL HAVING A BOILING POINT BELOW 150*C. FOR EACH MOL OF PENTAERYTHRITOL AND BETWEEN ABOUT 0.1 TO 10 PERCENT OF A TRANSESTERIFICATION CATALYST BASED UPON THE COMBINED WEIGHT OF PENTAERYTHRITOL AND SAID ESTER, B. HEATING THE REACTION MIXTURE TTO A TEMPERATURE BETWEEN 135* AND 170*C. TO PRODUCE TRANSESTERIFICATION BETWEEN THE PENTAERYTHRITOL AND SAID ESTER, C. REMOVING ALKANOL PRODUCED BY SAID TRANSESTERIFICATION FROM THE REACTION MIXTURE BY DISTILLATION, D. ADJUSTING THE TEMPERATURE OF THE RESULTING REACTION MASS TO BETWEEN 90* AND 150*C., AND E. SEPARATING PENTAERYTHRITOL TETRACARBAMATE EXISTING AS INSOLUBLE PRODUCT IN THE REACTION MASS FROM THE REMAINDER OF THE REACTION MASS EXISTING AS LIQUID PORTION AT SAID TEMPERATURE BETWEEN 90* AND 150*C.
Claim 2
Dependent Claim
141 words
A PROCESS FOR THE MANUFACTURE OF PENTAERYTHRITOL TETRACARBAMATE WHICH COMPRISES: A. PROVIDING A REACTION MIXTURE CONSISTING ESSENTIALLY OF PENTAERYTHRITOL, 6 TO 10 MOLS OF A CARBAMATE ESTER OF AN ALKANOL HAVING A BOILING POINT BELOW 150*C. FOR EACH MOL OF PENTAERYTHRITOL AND BETWEEN ABOUT 0.1 TO 10 PERCENT OF A TRANSESTERIFICATION CATALYST BASED UPON THE COMBINED WEIGHT OF PENTAERYTHRITOL AND SAID ESTER, B. HEATING THE REACTION MIXTURE TTO A TEMPERATURE BETWEEN 135* AND 170*C. TO PRODUCE TRANSESTERIFICATION BETWEEN THE PENTAERYTHRITOL AND SAID ESTER, C. REMOVING ALKANOL PRODUCED BY SAID TRANSESTERIFICATION FROM THE REACTION MIXTURE BY DISTILLATION, D. ADJUSTING THE TEMPERATURE OF THE RESULTING REACTION MASS TO BETWEEN 90* AND 150*C., AND E. SEPARATING PENTAERYTHRITOL TETRACARBAMATE EXISTING AS INSOLUBLE PRODUCT IN THE REACTION MASS FROM THE REMAINDER OF THE REACTION MASS EXISTING AS LIQUID PORTION AT SAID TEMPERATURE BETWEEN 90* AND 150*C.
Claim 3
Dependent Claim
122 words
A process for the manufacture of pentaerythritol tetracarbamate which comprises: a. providing a reaction mixture consisting essentially of pentaerythritol, 6 to 10 mols of ethyl carbamate for each mol of pentaerythritol and between about 0.1 to 10 percent of a transesterification catalyst based upon the combined weight of pentaerythritol and ethyl carbamate, b. heating the reaction mixture to a temperature to produce transesterification between pentaerythritol and ethyl carbamate, c. removing ethanol from the reaction mixture by distillation, d. adjusting the temperature of the resulting reaction mass to between 90* and 150*C, and e. separating pentaerythritol tetracarbamate existing as insoluble product in the reaction mass from the remainder of the reaction mass existing as liquid portion at said temperature between 90* and 150*C.
Claim 4
Dependent Claim
122 words
A process for the manufacture of pentaerythritol tetracarbamate which comprises: a. providing a reaction mixture consisting essentially of pentaerythritol, 6 to 10 mols of ethyl carbamate for each mol of pentaerythritol and between about 0.1 to 10 percent of a transesterification catalyst based upon the combined weight of pentaerythritol and ethyl carbamate, b. heating the reaction mixture to a temperature to produce transesterification between pentaerythritol and ethyl carbamate, c. removing ethanol from the reaction mixture by distillation, d. adjusting the temperature of the resulting reaction mass to between 90* and 150*C, and e. separating pentaerythritol tetracarbamate existing as insoluble product in the reaction mass from the remainder of the reaction mass existing as liquid portion at said temperature between 90* and 150*C.
Claim 5
Dependent Claim
12 words
The process of claim 1 wherein said catalyst is dibutyl tin oxide.
Claim 6
Dependent Claim
82 words
In the process of manufacture of pentaerythritol tetracarbamate by transesterification of pentaerythritol with a lower alkyl carbamate ester and lower alkanol is distilled from the reaction mixture leaving an alkanol denuded reaction mass, the improvement which comprises: A. adjusting the temperature of the denuded reaction mass to between 90* and 150*C, and B. separating pentaerythritol tetracarbamate existing as insoluble product in said reaction mass from the remainder of the reaction mass existing as liquid portion at said temperature between 90* and 150*C.
Claim 7
Dependent Claim
82 words
In the process of manufacture of pentaerythritol tetracarbamate by transesterification of pentaerythritol with a lower alkyl carbamate ester and lower alkanol is distilled from the reaction mixture leaving an alkanol denuded reaction mass, the improvement which comprises: A. adjusting the temperature of the denuded reaction mass to between 90* and 150*C, and B. separating pentaerythritol tetracarbamate existing as insoluble product in said reaction mass from the remainder of the reaction mass existing as liquid portion at said temperature between 90* and 150*C.
Claim 8
Dependent Claim
61 words
In the process of manufacture of pentaerythritol tetracarbamate by transesterification of pentaerythritol with ethyl carbamate and ethanol is distilled from the reaction mixture leaving an ethanol denuded reaction mass, the improvement which comprises: A. adjusting the temperature of the denuded reaction mass to about 90*C, and B. centrifuging the temperature adjusted reaction mass to recover pentaerythrital tetracarbamate as finely divided powder.
Claim 9
Dependent Claim
61 words
In the process of manufacture of pentaerythritol tetracarbamate by transesterification of pentaerythritol with ethyl carbamate and ethanol is distilled from the reaction mixture leaving an ethanol denuded reaction mass, the improvement which comprises: A. adjusting the temperature of the denuded reaction mass to about 90*C, and B. centrifuging the temperature adjusted reaction mass to recover pentaerythrital tetracarbamate as finely divided powder.
Claim 10
Dependent Claim
87 words
In the process of manufacture of pentaerythritol tetracarbamate by transesterification of pentaerythritol with a carbamate ester of a monohydric alcohol having a boiling point below 150*C and monohydric alcohol produced by the transesterification is distilled from the reaction mixture leaving an alcohol denuded reaction mass, the improvement which comprises: A. adjusting the temperature of the denuded reaction mass to between 90* and 150*C, and B. separating pentaerythritol tetracarbamate existing as insoluble product in the reaction mass existing as liquid portion at said temperature between 90* and 150*C.
Claim 11
Dependent Claim
87 words
In the process of manufacture of pentaerythritol tetracarbamate by transesterification of pentaerythritol with a carbamate ester of a monohydric alcohol having a boiling point below 150*C and monohydric alcohol produced by the transesterification is distilled from the reaction mixture leaving an alcohol denuded reaction mass, the improvement which comprises: A. adjusting the temperature of the denuded reaction mass to between 90* and 150*C, and B. separating pentaerythritol tetracarbamate existing as insoluble product in the reaction mass existing as liquid portion at said temperature between 90* and 150*C.
Claim 12
Dependent Claim
23 words
The process of claim 1 wherein said catalyst is selected from the group consisting of aluminum alkoxides, zinc oxide and dialkyl tin oxides.
References Cited (Backward Citations)
US2694690A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-09 | 1978-06-10 | 1978-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-09 | 1982-06-10 | 1982-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-09 | 1986-06-10 | 1986-12-10 | $7700.00 | Window Closed / Lapsed |