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US3723575A
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Method of producing graft polymers
Assignee: Bridgestone Firestone Inc
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Filing: 1971-04-14
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Granted: 1973-03-27
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Expires: 1991-04-14
Abstract
Abstract Graft polymers are produced by polymerizing a first monomer charge at a relatively low temperature, heat-treating the polymer, and charging additional monomer. The first monomer charge contains at least one conjugated diene of from four to eight carbons, and the first polymerization step is performed in the presence of a hydrocarbon lithium initiator. The heattreating step is performed on the base polymer at 70*-130* C. for 2 - 200 hours.
Inventors
- 👤 W Kern
- 👤 T Bouton
- 👤 H Adams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:41
CPC Classifications
C; C08; C08F; C08F297/00; C08F297/02; C08F297/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
18 words
The method of claim 1, wherein the conjugated diene monomer is isoprene or butadiene-1,3, or mixtures of both.
Claim 2
Dependent Claim
20 words
The method of claim 1, wherein the first monomer charge includes a vinyl aromatic monomer having up to 20 carbons.
Claim 3
Dependent Claim
12 words
The method of claim 3, wherein the vinyl aromatic monomer is styrene.
Claim 4
Dependent Claim
16 words
The method of claim 1, wherein an inert hydrocarbon diluent is present in the polymerization zone.
Claim 5
Dependent Claim
26 words
The method of claim 1, wherein the polymerization zone is maintained at a temperature of from 30* to 50* C. until a base polymer is formed.
Claim 6
Dependent Claim
10 words
The method of claim 1, wherein the initiator is n-butyllithium.
Claim 7
Dependent Claim
32 words
The method of claim 1, wherein the second charge of polymerizable monomer comprises a conjugated diene of from four to eight carbons or a vinyl aromatic monomer having up to 20 carbons.
Claim 8
Dependent Claim
27 words
The method of claim 1, wherein the second charge of polymerizable monomer comprises one or more halogen- or alkoxy-substituted conjugated dienes of from four to eight carbons.
Claim 9
Dependent Claim
32 words
The method of claim 1, wherein the second charge of polymerizable monomer comprises one or more vinyl aromatic monomers having up to 20 carbon atoms which monomers are halogen-, alkoxy- or amino-substituted.
Claim 10
Dependent Claim
23 words
The method of claim 1, wherein the second charge of polymerizable monomer comprisEs one or more acrylic or alkacrylic acid esters or nitriles.
References Cited (Backward Citations)
US3492369A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |