Patent US4272425A successfully refreshed from Google Patents.
US4272425A
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Treating dispersions of acrylonitrile polymers
Assignee: Goodrich Corp
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Filing: 1979-10-26
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Granted: 1981-06-09
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Expires: 1999-10-26
Abstract
Abstract Residual acrylonitrile dissolved in acrylonitrile copolymers and/or water in which acrylonitrile polymers are polymerized or processed such as a latex thereof or from acrylonitrile processes can be substantially reduced by adding to polymer-water mixtures for example, after at least 90% of the monomers have been polymerized, additional catalyst and an amount of comonomer in excess of the amount of free acrylonitrile present.
Inventors
- 👤 James R. Miller
- 👤 Edward J. Leeson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 23:09
CPC Classifications
C; C08; C08F; C08F6/00; C08F265/00; C08F265/08; C08F6/006
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
80 words
A method for reducing the acrylonitrile content of aqueous dispersions of copolymers of butadiene-1,3 and acrylonitrile comprising adding to said dispersion after the butadiene-1,3 and acrylonitrile have copolymerized to greater than 90% conversion to copolymer an amount of butadiene-1,3 greater than the amount of free acrylonitrile and a catalyst comprising an organic peroxide and a reducing heavy metal compound in amount based on the peroxy compound of at least about 0.1 part based on the total monomer and polymer present.
Claim 2
Independent Claim
80 words
A method for reducing the acrylonitrile content of aqueous dispersions of copolymers of butadiene-1,3 and acrylonitrile comprising adding to said dispersion after the butadiene-1,3 and acrylonitrile have copolymerized to greater than 90% conversion to copolymer an amount of butadiene-1,3 greater than the amount of free acrylonitrile and a catalyst comprising an organic peroxide and a reducing heavy metal compound in amount based on the peroxy compound of at least about 0.1 part based on the total monomer and polymer present.
Claim 3
Dependent Claim
48 words
A method of claim 1 wherein said butadiene is added in amounts greater than a 67 to 33 weight percent ratio of butadiene to acrylonitrile, said butadiene and catalyst addition being added after the conversion of the originally charged butadiene and acrylonitrile is greater than about 93% polymer.
Claim 4
Dependent Claim
28 words
A method of claim 1 wherein said butadiene and said redox catalyst are added when the copolymers have copolymerized to a conversion to polymer of greater than 93%.
Claim 5
Dependent Claim
35 words
A method of claim 3 wherein the temperature of addition of butadiene and redox catalyst is between about 25° to 60° C. and the amount of residual free acrylonitrile resulting is less than 100 ppm.
Claim 6
Dependent Claim
31 words
A method of claim 3 wherein the amount of butadiene and acrylonitrile initially copolymerized is from about 60 to 80 weight percent butadiene-1,3 and about 20 to 40 weight percent acrylonitrile.
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) | 1984-06-08 | 1984-12-08 | 1985-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-08 | 1988-12-08 | 1989-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-08 | 1992-12-08 | 1993-06-09 | $7700.00 | Window Closed / Lapsed |