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US4754017A
Expired / Lapsed
US
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Process for the preparation of linear aliphatic polycarbonate from cyclic aliphatic carbonate
Assignee: Bayer AG
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Filing: 1987-02-24
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Granted: 1988-06-28
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Expires: 2007-02-24
Abstract
Abstract Process for the polymerization of cyclic aliphatic carbonates in the presence of aprotic organic solvents with exclusion of atmospheric oxygen and atmospheric moisture, wherein organometallic compounds of elements of main group 1 of the periodic table are used as initiators, the monomer/solvent ratio is in the range from 1 part by weight to 50 parts by weight of monomer per 100 parts by weight of solvent and the polymerization temperature is between -100° C. and +20° C.
Inventors
- 👤 Edgar Leitz
- 👤 Christian Lindner
- 👤 Herbert Eichenauer
- 👤 Karl-Heinz Ott
- 👤 Hans-Josef Buysch
- 👤 Peter Mues
- 👤 Hartwig Hocker
- 👤 Helmut Keul
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:39
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/20; C08G64/30; C08G64/02; C08G64/0208
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
182 words
A process for the production of a linear aliphatic polycarbonate in which a cyclic aliphatic carbonate of the general formula (I) ##STR5## wherein R 1 denotes --(CH 2 ) n --, --CH 2 CH 2 CH(CH 3 )--, --CH 2 CH 2 OCH 2 CH 2 OCH 2 CH 2 --, ##STR6## wherein n is 3, 4, 5 or 6, or of the general formula (II) ##STR7## wherein R 2 denotes --(CH 2 ) m --, --CH 2 CH 2 OCH 2 CH 2 -- or --CH 2 CH 2 OCH 2 CH 2 OCH 2 CH 2 -- wherein m is an integer from 4 to 12, is polymerized in the presence of an aprotic organic solvent with the exclusion of atmospheric oxygen and atmospheric moisture, an organometallic compound of an element of main group 1 of the periodic table being used as initiator, the monomer/solvent ratio being in the range from 1 part by weight to 50 parts by weight of monomer per 100 parts by weight of solvent and the polymerization temperature being between -100° C. and +20° C.
Claim 2
Dependent Claim
182 words
A process for the production of a linear aliphatic polycarbonate in which a cyclic aliphatic carbonate of the general formula (I) ##STR5## wherein R 1 denotes --(CH 2 ) n --, --CH 2 CH 2 CH(CH 3 )--, --CH 2 CH 2 OCH 2 CH 2 OCH 2 CH 2 --, ##STR6## wherein n is 3, 4, 5 or 6, or of the general formula (II) ##STR7## wherein R 2 denotes --(CH 2 ) m --, --CH 2 CH 2 OCH 2 CH 2 -- or --CH 2 CH 2 OCH 2 CH 2 OCH 2 CH 2 -- wherein m is an integer from 4 to 12, is polymerized in the presence of an aprotic organic solvent with the exclusion of atmospheric oxygen and atmospheric moisture, an organometallic compound of an element of main group 1 of the periodic table being used as initiator, the monomer/solvent ratio being in the range from 1 part by weight to 50 parts by weight of monomer per 100 parts by weight of solvent and the polymerization temperature being between -100° C. and +20° C.
Claim 3
Dependent Claim
31 words
A process according to claim 1, in which the monomer/solvent weight ratio is 5 parts by weight to 20 parts by weight of monomer per 100 parts by weight of solvent.
Claim 4
Dependent Claim
21 words
A process according to claim 1, in which the polymerization temperature is in the range from -50° C. to 0° C.
Claim 5
Dependent Claim
18 words
A process according to claim 1, in which the cyclic aliphatic carbonate is of the formula (III) ##STR8##
Claim 6
Dependent Claim
14 words
A process according to claim 1, in which the initiator is n-butyllithium or sec.-butyllithium.
Claim 7
Dependent Claim
31 words
A process according to claim 1, in which the aprotic organic solvent is selected form aromatic hydrocarbons, aliphatic, hydrocarbons, cyclic ethers or mixtures of cyclic ethers with aromatic or aliphatic hydrocarbons.
Claim 8
Dependent Claim
15 words
A process according to claim 1, in which the aprotic solvent is toluene or tetrahydrofuran.
References Cited (Backward Citations)
US3220980A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-06-28 | 1991-12-28 | 1992-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-28 | 1995-12-28 | 1996-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-28 | 1999-12-28 | 2000-06-28 | $7700.00 | Window Closed / Lapsed |