Patent US4101533A successfully refreshed from Google Patents.
US4101533A
Expired / Lapsed
US
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Cyclic carbonic acid esters as solvents for poly-(β-hydroxybutyric acid
Assignee: Agroferm AG
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Filing: 1977-01-12
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Granted: 1978-07-18
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Expires: 1997-01-12
Abstract
Abstract The use of cyclic carbonic acid esters of the formula: ##STR1## wherein R 1 , R 2 , R 3 and R 4 , which may be the same or different, are hydrogen or alkyl with 1 to 6 C-atoms, as a solvent for racemic or optically active poly-(β-hydroxybutyric acid). The preferred embodiment uses hot (120° to 150° C) ethylene carbonate or 1,2-propylene carbonate to extract poly-(β-hydroxybutyric acid) from moist or dry fermentation masses. These solvents have the advantage that the extracted poly-(β-hydroxybutyric acid) is precipitated in good yield from them on cooling. In addition they may be recycled without the need for a solvent regeneration step. These cyclic carbonic acid esters may also be used as the solvent in the processing of poly-(β-hydroxybutyric acid) by e.g. wet spinning.
Inventors
- 👤 Robert M. Lafferty
- 👤 Elmar Heinzle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:54
CPC Classifications
C; C12; C12P; C12P7/00; C12P7/62; C12P7/625; Y; Y10; Y10S; Y10S435/00; Y10S435/8215; Y10S435/822; Y10S435/831; Y10S435/832; Y10S435/837
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
36 words
A process for the extraction of racemic or optically active poly-(β-hydroxybutyric acid) from a fermentaton mass which comprises: contacting a fermentation mass containing poly-(β-hydroxybutyric acid) with a liquid cyclic carbonic acid ester of the formula: ##STR3##
Claim 2
Dependent Claim
36 words
A process for the extraction of racemic or optically active poly-(β-hydroxybutyric acid) from a fermentaton mass which comprises: contacting a fermentation mass containing poly-(β-hydroxybutyric acid) with a liquid cyclic carbonic acid ester of the formula: ##STR3##
Claim 3
Dependent Claim
36 words
wherein R 1 , R 2 , R 3 and R 4 , which are the same or different, are hydrogen or alkyl with 1 to 6 carbon atoms, as a solvent for the poly-(β-hydroxybutyric acid.
Claim 4
Dependent Claim
36 words
wherein R 1 , R 2 , R 3 and R 4 , which are the same or different, are hydrogen or alkyl with 1 to 6 carbon atoms, as a solvent for the poly-(β-hydroxybutyric acid.
Claim 5
Dependent Claim
14 words
A process according to claim 1 in which the fermentation mass contains poly-(D-β-hydroxybutyric acid).
Claim 6
Dependent Claim
37 words
A process according to claim 1 in which the liquid cyclic carbonic acid ester solvent in contact with the fermentation mass is at an elevated temperature sufficient to promote solution of the poly-(β-hydroxybutyric acid) in the solvent.
Claim 7
Dependent Claim
36 words
A process according to claim 3 in which the solvent containing poly-(β-hydroxybutyric acid) is separated from the extracted fermentation mass, cooled to precipitate the poly-(β-hydroxybutyric acid) and the precipitated poly-(β-hydroxybutyric acid) is separated from the solvent.
Claim 8
Dependent Claim
25 words
A process according to claim 1 in which the fermentation mass is a moist or dry cell mass of a microorganism which forms poly-(β-hydroxybutyric acid).
Claim 9
Dependent Claim
37 words
A process according to claim 1 in which R 1 , R 2 , R 3 and R 4 , which may be the same or different, are hydrogen or alkyl with 1 to 4 carbon atoms.
Claim 10
Dependent Claim
37 words
A process according to claim 1 in which R 1 , R 2 , R 3 and R 4 , which may be the same or different, are hydrogen or alkyl with 1 to 2 carbon atoms.
Claim 11
Dependent Claim
19 words
A process according to claim 1 in which the solvent is ethylene carbonate, 1,2-propylene carbonate or a mixture thereof.
Claim 12
Dependent Claim
105 words
A process for the extracton of poly-(D-β-hydroxybutyric acid) from a moist or dry cell mass of a microorganism which forms poly-(D-β-hydroxybutyric acid), which comprises: suspending the cell mass in a liquid cyclic carbonic acid ester of the formula: ##STR4## wherein R 1 , R 2 , R 3 and R 4 , which are the same or different, are hydrogen or alkyl with 1 to 6 carbon atoms, as a solvent for the poly-(D-β-hydroxybutyric acid, heating the suspension with stirring to a temperature above 100° C., separating the cell mass from the hot solvent extract, and cooling the hot solvent extract to precipitate poly-(D-β-hydroxybutyric acid).
Claim 13
Dependent Claim
105 words
A process for the extracton of poly-(D-β-hydroxybutyric acid) from a moist or dry cell mass of a microorganism which forms poly-(D-β-hydroxybutyric acid), which comprises: suspending the cell mass in a liquid cyclic carbonic acid ester of the formula: ##STR4## wherein R 1 , R 2 , R 3 and R 4 , which are the same or different, are hydrogen or alkyl with 1 to 6 carbon atoms, as a solvent for the poly-(D-β-hydroxybutyric acid, heating the suspension with stirring to a temperature above 100° C., separating the cell mass from the hot solvent extract, and cooling the hot solvent extract to precipitate poly-(D-β-hydroxybutyric acid).
Claim 14
Dependent Claim
19 words
A process according to claim 9 in which the solvent is ethylene carbonate, 1,2-propylene carbonate or a mixture thereof.
Claim 15
Dependent Claim
17 words
A process according to claim 9 in which the suspension is heated to 100° to 150° C.
Claim 16
Dependent Claim
17 words
A process according to claim 9 in which the suspension is heated to 120° to 150° C.
Claim 17
Dependent Claim
22 words
A process according to claim 9 in which the cell mass is separated from the hot extract by decanting, filtering or centrifuging.
Claim 18
Dependent Claim
23 words
A process according to claim 9 in which water is added to the solvent extract after the extracted cell mass is separated therefrom.
References Cited (Backward Citations)
US3275610A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-07-17 | 1982-01-16 | 1982-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-17 | 1986-01-16 | 1986-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-17 | 1990-01-16 | 1990-07-18 | $7700.00 | Window Closed / Lapsed |