Patent US5134222A successfully refreshed from Google Patents.
US5134222A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Poly(butylene terephthalate) copolyester and a process for preparing it
Assignee: Invista North America LLC
•
Filing: 1991-12-23
•
Granted: 1992-07-28
•
Expires: 2011-12-23
Abstract
Abstract Poly(butylene terephthalate) copolyester advantageous of use as sheath materials in bicomponent fibers are prepared by a process for preparing a high-molecular weight, linear copolyester by condensing 40-85 molar percent of terephthalic acid optionally in the form of a dialkyl ester, half of which component can optionally be replaced by another dicarboxylic acid also optionally in the dialkyl ester form, and 60-15 molar percent of a blend of dimethyl adipate, dimethyl glutarate and dimethyl succinate with an alkanediol of 2-6 carbon atoms in its carbon chain, at an elevated temperature in the presence of a conventional catalyst, in a first condensation stage which is an interesterification or esterification stage and a second condensation stage which is a polycondensation stage, whereby a copolyester melt is produce. The process comprises, before or during the first condensation stage, adding 0.005-0.1 molar percent, based on the total acid component, of a C 6 -aryl or C 7 -alkaryl ester of phosphorous acid or of phosphoric acid to the reaction mixture.
Inventors
- 👤 A. Wayne Cooke
- 👤 Barrie L. Davies
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:43
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/87; C08G63/02; C08G63/12; C08G63/16; C08G63/68; C08G63/692; C08G63/6924; C08G63/6926; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31786
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
150 words
A process for preparing a copolyester by condensing 40-85 molar percent of terephthalic acid optionally in the form of a dialkyl ester, half of which component can optionally be replaced by another dicarboxylic acid also optionally in the dialkyl ester form, and 60-15 molar percent of a blended product of dimethyl adipate, dimethyl glutarate and dimethyl succinate with an alkanediol of 2-6 carbon atoms in its carbon chain, at an elevated temperature in the presence of a conventional catalyst, in a first condensations stage which is an interesterification or esterification stage and a second condensation stage which is a polycondensation stage, whereby a copolyester melt is produced, which comprises, before or during the first condensation stage, adding 0.005-0.1 molar percent, based on the total acid component, of a C 6-10 -aryl or C 7-20 -alkaryl ester of phosphorous acid or of phosphoric acid including polyphosphoric acid to the reaction mixture.
Claim 2
Dependent Claim
150 words
A process for preparing a copolyester by condensing 40-85 molar percent of terephthalic acid optionally in the form of a dialkyl ester, half of which component can optionally be replaced by another dicarboxylic acid also optionally in the dialkyl ester form, and 60-15 molar percent of a blended product of dimethyl adipate, dimethyl glutarate and dimethyl succinate with an alkanediol of 2-6 carbon atoms in its carbon chain, at an elevated temperature in the presence of a conventional catalyst, in a first condensations stage which is an interesterification or esterification stage and a second condensation stage which is a polycondensation stage, whereby a copolyester melt is produced, which comprises, before or during the first condensation stage, adding 0.005-0.1 molar percent, based on the total acid component, of a C 6-10 -aryl or C 7-20 -alkaryl ester of phosphorous acid or of phosphoric acid including polyphosphoric acid to the reaction mixture.
Claim 3
Dependent Claim
24 words
A process of claim 1, wherein before or during the first condensation stage, 0.01-0.06 molar percent of the aryl or alkaryl ester is added.
Claim 4
Dependent Claim
19 words
A process of claim 1 wherein the aryl or alkaryl ester is triphenyl, tri-tertbutylphenyl, trinonylphenyl or tricresylphosphates or phosphites.
Claim 5
Dependent Claim
12 words
A process of claim 1 wherein triphenyl phosphate is the aryl ester.
Claim 6
Dependent Claim
12 words
A high molecular weight copolyester prepared by the process of claim 1.
Claim 7
Dependent Claim
94 words
A process for preparing a poly(butylene terephthalate) (PBT) copolymer by condensing 40-85 molar percent of dimethyl terephthalate (DMT); and 60-15 molar percent of a blended product of dimethyl adipate, dimethyl glutarate and dimethyl succinate; with butanediol and hexanediol, at an elevated temperature in the presence of a conventional catalyst, in a first condensation stage which is an ester interchange stage and a second condensation stage which is a polycondensation stage, whereby the PBT copolymer is produced, which comprises before or during the ester interchange stage adding 0.005-0.1 molar percent triphenyl phosphate based on DMT.
Claim 8
Dependent Claim
94 words
A process for preparing a poly(butylene terephthalate) (PBT) copolymer by condensing 40-85 molar percent of dimethyl terephthalate (DMT); and 60-15 molar percent of a blended product of dimethyl adipate, dimethyl glutarate and dimethyl succinate; with butanediol and hexanediol, at an elevated temperature in the presence of a conventional catalyst, in a first condensation stage which is an ester interchange stage and a second condensation stage which is a polycondensation stage, whereby the PBT copolymer is produced, which comprises before or during the ester interchange stage adding 0.005-0.1 molar percent triphenyl phosphate based on DMT.
References Cited (Backward Citations)
US4328059A
Cited
US4559370A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-07-28 | 1996-01-27 | 1996-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-07-28 | 2000-01-27 | 2000-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-07-28 | 2004-01-27 | 2004-07-28 | $7700.00 | Window Closed / Lapsed |