US4020049A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing polyester resin
Assignee: Shell USA Inc
•
Filing: 1971-04-02
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Granted: 1977-04-26
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Expires: 1991-04-02
Abstract
Abstract The invention is a process for reacting organic dicarboxylic acid and glycol under pressure and at elevated temperature in the presence of low molecular weight polyester resin to produce low molecular weight polyester resin product which can be polymerized to high molecular weight polyester resin. The process can be operated batchwise or continuously.
Inventors
- 👤 Verne R. Rinehart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:22
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
129 words
The method for the commercial scale production of polyesters which comprises adding commercial scale quantities of ethylene glycol and a free aromatic dicarboxylic acid in the molar ratio of glycol to acid of from 1.7:1 to 1.05:1 to a solvent consisting of a preformed low molecular weight linear condensation polyester of a glycol and a dicarboxylic acid, said polyester having an average degree of polymerization of from 1.4 to 10, heating and reacting the mixture at a temperature above the melting temperature of the low molecular weight linear polyester at a pressure of from about 20 to about 1000 pounds per square inch gauge pressure until a linear condensation polyester resin of said glycol and acid having an average degree of polymerization of from 1.4 to 10 is formed.
Claim 2
Independent Claim
129 words
The method for the commercial scale production of polyesters which comprises adding commercial scale quantities of ethylene glycol and a free aromatic dicarboxylic acid in the molar ratio of glycol to acid of from 1.7:1 to 1.05:1 to a solvent consisting of a preformed low molecular weight linear condensation polyester of a glycol and a dicarboxylic acid, said polyester having an average degree of polymerization of from 1.4 to 10, heating and reacting the mixture at a temperature above the melting temperature of the low molecular weight linear polyester at a pressure of from about 20 to about 1000 pounds per square inch gauge pressure until a linear condensation polyester resin of said glycol and acid having an average degree of polymerization of from 1.4 to 10 is formed.
Claim 3
Dependent Claim
45 words
The process of claim 1 in which the water formed in the esterification reaction is distilled out of the mixture at such a rate that the pressure is maintained within the range of from about 20 to about 1000 pounds per square inch gauge pressure.
Claim 4
Independent Claim
100 words
The method for the commercial scale production of a low molecular weight ethylene glycol-terephthalate polyester which comprises adding commercial scale quantities of ethylene glycol and terephthalic acid in the ratio of from 1.7:1 to 1.05:1 of ethylene glycol to terephthalic acid to a solvent consisting of low molecular weight ethylene glycol-terephthalate polyester having an average degree of polymerization of from 1.4 to 10, heating and reacting the mixture at a temperature above the melting temperature of the low molecular weight ethylene glycol-terephthalate polyester at a pressure range of from about 20 to about 1000 pounds per square inch gauge pressure.
Claim 5
Independent Claim
100 words
The method for the commercial scale production of a low molecular weight ethylene glycol-terephthalate polyester which comprises adding commercial scale quantities of ethylene glycol and terephthalic acid in the ratio of from 1.7:1 to 1.05:1 of ethylene glycol to terephthalic acid to a solvent consisting of low molecular weight ethylene glycol-terephthalate polyester having an average degree of polymerization of from 1.4 to 10, heating and reacting the mixture at a temperature above the melting temperature of the low molecular weight ethylene glycol-terephthalate polyester at a pressure range of from about 20 to about 1000 pounds per square inch gauge pressure.
Claim 6
Independent Claim
146 words
The method for the commercial scale production of polyesters which comprises continuously adding commercial scale quantities of ethylene glycol and terephthalic acid in the ratio of from 1.7:1 to 1.05:1 of ethylene glycol to terephthalic acid to a solvent consisting of low molecular weight ethylene glycol-terephthalate polyester having an average degree of polymerization of from 1.4 to 10 while heating and reacting the mixture at a temperature above the melting temperature of the low molecular weight ethylene glycol-terephthalate polyester at a pressure range of from about 20 to about 1000 pounds per square inch gauge pressure, continuously venting the water vapor formed in the reaction at such a rate that the pressure in the system is maintained constant within said pressure range and continuously withdrawing an amount of low molecular weight ethylene glycol-terephthalate polyester about equal to the amount of ethylene glycol and terephthalic acid added.
Claim 7
Independent Claim
146 words
The method for the commercial scale production of polyesters which comprises continuously adding commercial scale quantities of ethylene glycol and terephthalic acid in the ratio of from 1.7:1 to 1.05:1 of ethylene glycol to terephthalic acid to a solvent consisting of low molecular weight ethylene glycol-terephthalate polyester having an average degree of polymerization of from 1.4 to 10 while heating and reacting the mixture at a temperature above the melting temperature of the low molecular weight ethylene glycol-terephthalate polyester at a pressure range of from about 20 to about 1000 pounds per square inch gauge pressure, continuously venting the water vapor formed in the reaction at such a rate that the pressure in the system is maintained constant within said pressure range and continuously withdrawing an amount of low molecular weight ethylene glycol-terephthalate polyester about equal to the amount of ethylene glycol and terephthalic acid added.
Claim 8
Dependent Claim
38 words
The method of claim 4 in which a condensation polymerization catalyst is added to the portion of low molecular weight polyester withdrawn and the low molecular weight polyester is polymerized to a high molecular weight polyester by condensation.
Claim 9
Independent Claim
180 words
The method for the commercial scale production of a highly polymeric linear polyester which comprises adding commercial scale quantities of (A) at least one acid selected from the group consisting of terephthalic acid, isophthalic acid and 2,6-naphthalic acid and (B) ethylene glycol in the molar ratio of glycol to acid of from 1.7:1 to 1.05:1 to a solvent consisting of a low molecular weight linear condensation polyester of a dicarboxylic acid of (A) and ethylene glycol, heating and reacting the mixture in the range of from the melting temperature of the low molecular weight linear polyester to 300° C at a pressure of from about 20 to about 1000 pounds per square inch gauge pressure distilling out the water formed in the reaction at such a rate that the pressure in the system remains constant within said pressure range, adding a condensation polymerization catalyst and then heating and reacting the mixture at a temperature of from about 265° C to 280° C at a pressure of about one millimeter of mercury until a high molecular weight linear polyester is formed.
Claim 10
Independent Claim
180 words
The method for the commercial scale production of a highly polymeric linear polyester which comprises adding commercial scale quantities of (A) at least one acid selected from the group consisting of terephthalic acid, isophthalic acid and 2,6-naphthalic acid and (B) ethylene glycol in the molar ratio of glycol to acid of from 1.7:1 to 1.05:1 to a solvent consisting of a low molecular weight linear condensation polyester of a dicarboxylic acid of (A) and ethylene glycol, heating and reacting the mixture in the range of from the melting temperature of the low molecular weight linear polyester to 300° C at a pressure of from about 20 to about 1000 pounds per square inch gauge pressure distilling out the water formed in the reaction at such a rate that the pressure in the system remains constant within said pressure range, adding a condensation polymerization catalyst and then heating and reacting the mixture at a temperature of from about 265° C to 280° C at a pressure of about one millimeter of mercury until a high molecular weight linear polyester is formed.
Claim 11
Independent Claim
113 words
The method for the commercial scale production of a linear polyester which comprises adding commercial scale quantities of (A) at least one acid selected from the group consisting of terephthalic acid, isophthalic acid and 2,6-naphthalic acid and (B) ethylene glycol in the molar ratio of glycol to acid of from 1.7:1 to 1.05:1 to a solvent consisting of a low molecular weight linear condensation polyester of a dicarboxylic acid of (A) and ethylene glycol, heating and reacting the mixture in the range of from the melting temperature of the low molecular weight linear polyester to 300° C at a pressure of from about 20 to about 1000 pounds per square inch gauge pressure.
Claim 12
Independent Claim
113 words
The method for the commercial scale production of a linear polyester which comprises adding commercial scale quantities of (A) at least one acid selected from the group consisting of terephthalic acid, isophthalic acid and 2,6-naphthalic acid and (B) ethylene glycol in the molar ratio of glycol to acid of from 1.7:1 to 1.05:1 to a solvent consisting of a low molecular weight linear condensation polyester of a dicarboxylic acid of (A) and ethylene glycol, heating and reacting the mixture in the range of from the melting temperature of the low molecular weight linear polyester to 300° C at a pressure of from about 20 to about 1000 pounds per square inch gauge pressure.
Claim 13
Dependent Claim
19 words
The method of claim 7 wherein said pressure is from 20 to about 100 pounds per square inch gauge.
Claim 14
Dependent Claim
47 words
The method of claim 4 wherein said water vapor formed from said reaction carries with it and forms a mixture with ethylene glycol, said water vapor-ethylene glycol mixture is passed through a condenser to condense ethylene glycol, and said ethylene glycol is returned to the reacting mixture.
Claim 15
Dependent Claim
20 words
The method of claim 3 wherein said pressure is from about 20 to about 100 pounds per square inch gauge.
Claim 16
Dependent Claim
29 words
The method of claim 3 comprising adding said ethylene glycol and terephthalic acid to said low molecular weight ethylene glycol-terephthalate polyester while said polyester is in a molten condition.
Claim 17
Dependent Claim
28 words
The method of claim 4 comprising adding said ethylene glycol and terephthalic acid to said low molecular weight ethylene-terephthalate polyester while said polyester is in a molten condition.
Claim 18
Dependent Claim
28 words
The method of claim 3 wherein the amount of solvent consisting of said ethylene glycol-terephthalate polyester is greater than the amount of said ethylene glycol and terephthalic acid.
Claim 19
Dependent Claim
33 words
The method of claim 7 wherein the amount of solvent consisting of a low molecular weight polyester is about 55% by weight based on the weight of said polyester, ethylene glycol and acid.
Claim 20
Dependent Claim
15 words
The method of claim 3 wherein said degree of polymerization is about 1.6 to 5.
Claim 21
Dependent Claim
40 words
The method of claim 4 wherein the pressure is at least as high as the vapor pressure of the glycol in the reaction mixture at the temperature used and less than the vapor pressure of water at the reaction temperature.
References Cited (Backward Citations)
CA574056A
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CA783594A
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GB764964A
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GB778410A
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US2921051A
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GB776282A
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US3050533A
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US3028366A
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US3427287A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-04-25 | 1980-10-25 | 1981-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-04-25 | 1984-10-25 | 1985-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-04-25 | 1988-10-25 | 1989-04-26 | $7700.00 | Window Closed / Lapsed |