Patent US3867349A successfully refreshed from Google Patents.
US3867349A
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Addition of dimethyl terephthalate and ethylene glycol to recycled bis(hydroxyethyl)terephthalate
Assignee: Davy Ashmore AG
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Filing: 1973-05-03
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Granted: 1975-02-18
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Expires: 1993-05-03
Abstract
Abstract An improved process for the production of high polymer polyesters wherein the dicarboxylic acid ester is added, as a finely divided solid, to a portion of the reaction product withdrawn from the ester interchange reaction and the resultant mixture is recycled back to the ester interchange reaction.
Inventors
- 👤 Rudolf Heeg
- 👤 Alfred Striebich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:08
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/785
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
137 words
IN A PROCESS FOR PRODUCING A HIGH-POLYMER PARTICULARLY A SPINNABLE, POLYESTER COMPOSITION BY ESTER INTERCHANGE OF DIMETHYL TEREPHTHALATE WITH ETHYLENE GLYCOL AS STARTING MATERIALS TO PRODUCE BIS-(2-HYDROXYETHYL)-TEREPHTHALATE AND SUBSEQUENT POLYCONDENSATION OF THE ESTER INTERCHANGE PRODUCT, IN WHICH THE DIMETHYL TEREPHTHALATE IS SUPPLIED TO THE ESTER INTERCHANGE STAGE IN A FINELY DIVIDED STATE FOR REACTION WITH THE ETHYLENE GLYCOL, THE IMPROVED PROCESS WHICH COMPRISES STEADILY WITHDRAWING A PART OF THE REACTION MIXTURE FROM THE ESTER INTERCHANGE STAGE, MAINTAINING THE WITHDRAWN MIXTURE AT A TEMPERATURE ABOVE THE MELTING POINT OF THE DIMETHYL TEREPHATHALATE, CONTINUOUSLY ADDING THE DIMETHYL TEREPHTHALATE IN SOLID FORM TO THE WITHDRAWN MIXTURE, HOMOGENIZING THE ADDED DIMETHYL TEREPHTHALATE AND WITHDRAWN MIXTURE IN A HOMOGENIZATION DEVICE TO FORM A HOMGENIZE MIXTURE OF DIMETHYL TEREPHTHALATE AND REACTION MIXTURE, AND RETURNING THE RESULTANT HOMOGENIZED MIXTURE TO THE ESTER INTERCHANGE STAGE.
Claim 2
Dependent Claim
137 words
IN A PROCESS FOR PRODUCING A HIGH-POLYMER PARTICULARLY A SPINNABLE, POLYESTER COMPOSITION BY ESTER INTERCHANGE OF DIMETHYL TEREPHTHALATE WITH ETHYLENE GLYCOL AS STARTING MATERIALS TO PRODUCE BIS-(2-HYDROXYETHYL)-TEREPHTHALATE AND SUBSEQUENT POLYCONDENSATION OF THE ESTER INTERCHANGE PRODUCT, IN WHICH THE DIMETHYL TEREPHTHALATE IS SUPPLIED TO THE ESTER INTERCHANGE STAGE IN A FINELY DIVIDED STATE FOR REACTION WITH THE ETHYLENE GLYCOL, THE IMPROVED PROCESS WHICH COMPRISES STEADILY WITHDRAWING A PART OF THE REACTION MIXTURE FROM THE ESTER INTERCHANGE STAGE, MAINTAINING THE WITHDRAWN MIXTURE AT A TEMPERATURE ABOVE THE MELTING POINT OF THE DIMETHYL TEREPHATHALATE, CONTINUOUSLY ADDING THE DIMETHYL TEREPHTHALATE IN SOLID FORM TO THE WITHDRAWN MIXTURE, HOMOGENIZING THE ADDED DIMETHYL TEREPHTHALATE AND WITHDRAWN MIXTURE IN A HOMOGENIZATION DEVICE TO FORM A HOMGENIZE MIXTURE OF DIMETHYL TEREPHTHALATE AND REACTION MIXTURE, AND RETURNING THE RESULTANT HOMOGENIZED MIXTURE TO THE ESTER INTERCHANGE STAGE.
Claim 3
Dependent Claim
35 words
A process according to claim 1, wherein the dimethyl terephthalate is mixed intimately with ethylene glycol in a mixing zone to form a paste prior to feeding the dimethyl terephthalate into the withdrawn reaction mixture.
Claim 4
Dependent Claim
37 words
A process according to claim 1, wherein the dimethyl terephthalate is admixed with ethylene glycol before combining the dimethyl terephthalate with the part of the withdrawn reaction mixture inside the homogenizing device whereby a paste is formed.
Claim 5
Dependent Claim
31 words
A process according to claim 1, wherein the process is a continuous process and the ratio of the withdrawn reaction mixture to the added starting materials is between 3.2:1 and 100:
Claim 6
Dependent Claim
22 words
A process according to claim 4, wherein the ratio of withdrawn reaction mixture to added starting materials is between 6.5:1 and 40:1.
Claim 7
Dependent Claim
31 words
A process according to claim 1, wherein the process is a discontinuous process and the ratio of the withdrawn reaction mixture to the added starting materials is between 1.3:1 and 100:
Claim 8
Dependent Claim
22 words
A process according to claim 6, wherein the ratio of withdrawn reaction mixture to added starting materials is between 2.1:1 and 40:1.
Claim 9
Dependent Claim
20 words
A process according to claim 1, wherein the temperature of the withdrawn reaction mixture is maintained between 140* and 250*C.
Claim 10
Dependent Claim
14 words
A process according to claim 8, wherein the temperature is between 160*C and 240*C.
Claim 11
Dependent Claim
34 words
A process according to claim 1, wherein the process is a continuous process and the ratio of the part circulated per hour to the content of the ester interchange stage is 0.6 to 150.
Claim 12
Dependent Claim
13 words
A process according to claim 10, wherein the ratio is 1.2 to 70.
Claim 13
Dependent Claim
34 words
A process according to claim 1, wherein the process is a discontinuous process and the ratio of the part circulated per hour to the content of the ester interchange stage is 0.25 to 150.
Claim 14
Dependent Claim
13 words
A process according to claim 12, wherein the ratio is 0.4 to 70.
Claim 15
Dependent Claim
15 words
A process according to claim 1 wherein said homogenizing device is a multi-stage tooth-disk mill.
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) | 1978-02-17 | 1978-08-19 | 1979-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-17 | 1982-08-19 | 1983-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-17 | 1986-08-19 | 1987-02-18 | $7700.00 | Window Closed / Lapsed |