US4518753A
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US
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Anionic polymerization of conjugated dienes in the presence of hindered triaryl boron or aluminum derivatives
Assignee: NATIONAL RESEARCH DEVELOPMENT Corp 101 NEWINGTON CAUSEWAY LONDON SE1 6UP ENGLAND
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Filing: 1983-04-15
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Granted: 1985-05-21
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Expires: 2003-04-15
Abstract
Abstract A process for the anionic polymerization of a conjugated 1,3-diene in a polar solvent consists of contacting the 1,3-diene with an organo alkali or alkaline earth metal initiator and a sterically hindered Lewis acid, allowing the 1,3-diene to polymerize in the polar solvent and terminating the polymerization reaction. Preferably the Lewis acid is a substituted triaryl derivative of a Group III element, especially boron. However in certain cases (e.g. where the aryl derivative itself is large) the Lewis acid may be an unsubstituted triaryl derivative of a Group III element. Suitable Lewis acids include trimesityl boron and tri (2,6-dimethylphenyl) boron. In preferred embodiments of the present process the 1,3-diene is butadiene, the polar solvent is tetrahydrofuran and the initiator is a difunctional initiator, especially an electron transfer reagent. The main advantages of the present process are that polymers with enhanced 1,4-content, a narrow molecular weight distribution and, in the case of telechelic polymers, with an enhanced difunctional specificity are obtained.
Inventors
- 👤 David H. Richards
- 👤 Malcolm J. Stewart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:39
CPC Classifications
C; C08; C08F; C08F36/00; C08F36/02; C08F36/04
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
95 words
A process for the production of a diene polymer having a relatively narrow molecular weight range by the anionic polymerisation of a conjugated 1,3-diene in a polar solvent wherein the 1,4-content of the polymer is enhanced and is at least about 20%, comprising: (a) contacting the 1,3-diene with an organo alkali or alkaline earth metal initiator in the presence of a sterically hindered triaryl derivative of a group III element which is boron or aluminum, (b) allowing the 1,3-diene to polymerise in a polymerisation reaction in the polar solvent, and (c) terminating the polymerisation reaction.
Claim 2
Dependent Claim
95 words
A process for the production of a diene polymer having a relatively narrow molecular weight range by the anionic polymerisation of a conjugated 1,3-diene in a polar solvent wherein the 1,4-content of the polymer is enhanced and is at least about 20%, comprising: (a) contacting the 1,3-diene with an organo alkali or alkaline earth metal initiator in the presence of a sterically hindered triaryl derivative of a group III element which is boron or aluminum, (b) allowing the 1,3-diene to polymerise in a polymerisation reaction in the polar solvent, and (c) terminating the polymerisation reaction.
Claim 3
Dependent Claim
13 words
A process according to claim 1 wherein the Group III element is boron.
Claim 4
Dependent Claim
24 words
A process according to claim 2 wherein the triaryl derivative comprises a triaryl boron derivative selected from the group consisting of tri(2,4,6-trimethylphenyl)boron and tri(2,6-dimethylphenyl)boron.
Claim 5
Dependent Claim
13 words
A process according to claim 1 where the Group III element is aluminium.
Claim 6
Dependent Claim
19 words
A process according to claim 1 wherein the conjugated 1,3-diene contains from 4 to 12 carbon atoms per molecule.
Claim 7
Dependent Claim
18 words
A process according to claim 5 wherein the conjugated 1,3-diene contains from 4 to 8 atoms per molecule.
Claim 8
Dependent Claim
12 words
A process according to claim 6 wherein the conjugated 1,3-diene comprises 1,3-butadiene.
Claim 9
Dependent Claim
23 words
A process according to claim 6 wherein the conjugated diene comprises a diene selected from the group consisting of isoprene, 2,3-dimethyl-1,3-butadiene and 1,3-pentadiene.
Claim 10
Dependent Claim
19 words
A process according to claim 1 wherein the organo alkali or alkaline earth metal initiator is a difunctional initiator.
Claim 11
Dependent Claim
31 words
A process according to claim 9 wherein the organo alkali or alkaline earth metal initiator comprises a reagent selected from the group consisting of alkyl lithium, alkyl sodium and aryl sodium.
Claim 12
Dependent Claim
31 words
A process according to claim 10 wherein the organo alkali or alkaline earth metal initiator is selected from the group consisting of the disodium tetramer of α-methylstyrene, sodium naphthalene and 1,4-dilithiobutane.
Claim 13
Dependent Claim
26 words
A process according to claim 1 wherein the polar solvent comprises a solvent selected from the group consisting of an alkyl ether and a cycloalkyl ether.
Claim 14
Dependent Claim
11 words
A process according to claim 12 wherein the solvent comprises tetrahydrofuran.
Claim 15
Dependent Claim
24 words
A process according to claim 12 wherein the polar solvent comprises a solvent selected from the group consisting of diethyl ether and diisopropyl ether.
Claim 16
Dependent Claim
23 words
A process according to claim 1 wherein the molar ratio of initiator to diene is between 15 to 1000 and 35 to 1000.
Claim 17
Dependent Claim
24 words
A process according to claim 1 wherein the molar ratio of triaryl derivative to initiator is between 2 to 1 and 10 to 1.
Claim 18
Dependent Claim
25 words
A process according to claim 1 wherein the polymerisation reaction is terminated by adding a proton donor or a functionalising reagent to the reaction mixture.
Claim 19
Dependent Claim
21 words
A process according to claim 17 wherein the proton donor is selected from the group consisting of water and alkyl alcohol.
Claim 20
Dependent Claim
42 words
A process according to claim 17 wherein the functionalising reagent is selected from the group consisting of carbon dioxide, an aldehyde, a ketone, an alkylene oxide, sulphur, a cyclic disulphide, a cyclic sulphide, an aminoaldehyde, a polyaziridine, a diepoxide and a glycidaldehyde.
Claim 21
Dependent Claim
12 words
A novel polymer whenever produced by a process according to claim 1.
Claim 22
Dependent Claim
13 words
A novel telechelic polymer whenever produced by a process according to claim 1.
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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) | 1988-05-20 | 1988-11-19 | 1989-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-20 | 1992-11-19 | 1993-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-20 | 1996-11-19 | 1997-05-21 | $7700.00 | Window Closed / Lapsed |