US3725360A
Expired / Lapsed
US
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Process for polymerizing styrene and maleic anhydride
Assignee: Dow Chemical Co
•
Filing: 1971-03-11
•
Granted: 1973-04-03
•
Expires: 1991-03-11
Abstract
Abstract High yields, without the application of heat, are obtained when styrene and maleic anhydride are polymerized in the presence of a tertiary aliphatic mercaptan and certain metals. Preferably the monomers are dissolved in a halogenated aliphatic hydrocarbon solvent.
Inventors
- 👤 J Adams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:40
CPC Classifications
C; C08; C08F; C08F222/00; C08F222/04; C08F222/06; C08F222/08
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
27 words
The process of claim 1 wherein said monomers are dissolved in a halogenated aliphatic hydrocarbon having no more than two halogens attached to any one carbon atom.
Claim 2
Dependent Claim
15 words
The process of claim 2 wherein said solvent is ethylene chloride, methylene chloride or trichloroethane.
Claim 3
Dependent Claim
13 words
The process of claim 2 wherein said monomers are styrene and maleic anhydride.
Claim 4
Dependent Claim
14 words
The process of claim 2 wherein said monomers are styrene, maleic anhydride and acrylonitrile.
Claim 5
Dependent Claim
12 words
The process of claim 2 wherein said metal is a halide salt.
Claim 6
Dependent Claim
12 words
The process of claim 6 wherein said salt is FeCl3 or CuCl.
Claim 7
Dependent Claim
14 words
The process of claim 2 wherein said mercaptan is t-butyl, t-amyl or t-dodecyl mercaptan.
Claim 8
Dependent Claim
13 words
The process of claim 1 wherein said monomers are styrene and maleic anhydride.
Claim 9
Dependent Claim
12 words
The process of claim 1 wherein said metal is a halide salt.
Claim 10
Dependent Claim
12 words
The process of claim 10 wherein said salt is FeCl3 or CuCl.
Claim 11
Dependent Claim
16 words
The process of claim 1 wherein said mercaptan has from five to about 15 carbon atoms.
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) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |