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US4048420A
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Polymerizations catalyzed by very finely divided lithium
Assignee: Bpifrance Financement SA
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Filing: 1976-01-30
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Granted: 1977-09-13
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Expires: 1996-01-30
Abstract
Abstract Polymerizations catalyzed by very finely divided lithium.
Inventors
- 👤 Bernard Francois
- 👤 Michel Vernois
- 👤 Emile Franta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:15
CPC Classifications
C; C08; C08F; C08F4/00; C08F4/42; C08F4/44; C08F4/46; C08F4/48; C08F4/482; C08F36/00; C08F36/02; C08F36/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
57 words
In a process for the polymerization of monomers comprising reacting at least one conjugated dienic monomer in the presence of an inert solvent and suspended lithium as a polymerization initiator at a temperature between about -40° C to +25° C, the improvement consisting of employing lithium having an average particle diameter of less than about 2 μ.
Claim 2
Dependent Claim
57 words
In a process for the polymerization of monomers comprising reacting at least one conjugated dienic monomer in the presence of an inert solvent and suspended lithium as a polymerization initiator at a temperature between about -40° C to +25° C, the improvement consisting of employing lithium having an average particle diameter of less than about 2 μ.
Claim 3
Dependent Claim
17 words
A process according to claim 1, wherein the average particle diameter of lithium is less than 0.1μ.
Claim 4
Dependent Claim
33 words
A process according to claim 1, wherein the lithium particles are first deposited on a divided substrate such as small sized solid bodies and thereafter suspended in said inert solvent before said polymerization.
Claim 5
Dependent Claim
32 words
A process according to claim 3, wherein the lithium particles are deposited on glass balls of an average diameter in the range of 2 to 0.2 mm and preferably of 5/10 mm.
Claim 6
Dependent Claim
22 words
A process according to claim 1, wherein the monomer is a diene monomer selected from the group consisting of isoprene or 1,3-butadiene.
Claim 7
Dependent Claim
26 words
A process according to claim 1, wherein an additional vinyl monomer is present selected from the group consisting of styrene and its alkyl derivatives or acrylonitrile.
Claim 8
Dependent Claim
25 words
α-ω dilithic polymers, such polymers being soluble, notably in a non-polar solvent, or in the form of gels, produced by the process of claim 1.
Claim 9
Dependent Claim
27 words
α-ω dilithic polymers according to claim 7, wherein the concentrations of dilithic extremities is 5·10 -3 mole/liter or higher, and more particularly higher than 10 -2 mole/liter.
Claim 10
Dependent Claim
11 words
Polymers according to claim 7, consisting of polybutadienyl-dilithium or polyisoprenyl-dilithium products.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-09-12 | 1981-03-14 | 1981-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-12 | 1985-03-14 | 1985-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-12 | 1989-03-14 | 1989-09-13 | $7700.00 | Window Closed / Lapsed |