Patent US4187363A successfully refreshed from Google Patents.
US4187363A
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Vinyl chloride polymerization method
Assignee: Geon Co
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Filing: 1978-05-24
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Granted: 1980-02-05
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Expires: 1998-05-24
Abstract
Abstract A method of achieving chain transfer in the polymerization of a vinyl chloride monomer to polyvinyl chloride, utilizing aldehydes of 3 to 6 carbon atoms as the chain transfer agent and treating the polymerization mixture with an alkali bisulfite, such as sodium bisulfite or potassium bisulfite solution after the vinyl chloride monomer has been stripped from the polymerization mixture to obtain modified polyvinyl chloride having improved compounded physical properties.
Inventors
- 👤 Richard A. Marshall
- 👤 Edwin S. Smith
- 👤 Frank A. Cich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:48
CPC Classifications
C; C08; C08F; C08F14/00; C08F14/02; C08F14/04; C08F14/06
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
65 words
A method of achieving chain transfer in a suspension polymerization of a vinyl chloride monomer to a polyvinyl chloride product comprising polymerizing said monomer in the presence of a peroxide catalyst and aldehydes of 3 to 6 carbon atoms as the chain transfer agent and treating product with an alkali bisulfite solution after the vinyl chloride monomer has been removed to obtain the polyvinyl chloride.
Claim 2
Independent Claim
65 words
A method of achieving chain transfer in a suspension polymerization of a vinyl chloride monomer to a polyvinyl chloride product comprising polymerizing said monomer in the presence of a peroxide catalyst and aldehydes of 3 to 6 carbon atoms as the chain transfer agent and treating product with an alkali bisulfite solution after the vinyl chloride monomer has been removed to obtain the polyvinyl chloride.
Claim 3
Dependent Claim
17 words
The method of claim 1 wherein the aldehyde is isobutyraldehyde and the alkali bisulfite is sodium bisulfite.
References Cited (Backward Citations)
US2414934A
Cited
US4060677A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-02-04 | 1983-08-06 | 1984-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-02-04 | 1987-08-06 | 1988-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-02-04 | 1991-08-06 | 1992-02-05 | $7700.00 | Window Closed / Lapsed |