US4478986A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tri-N-substituted-s-triazine-trione chain terminator for polyvinyl chloride polymerization
Assignee: Kloeckner Humboldt Deutz AG
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Filing: 1982-09-16
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Granted: 1984-10-23
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Expires: 2002-09-16
Abstract
Abstract An improved process for terminating the suspension polymerization reaction of vinyl chloride monomer into polyvinyl chloride which comprises adding hindered phenols of the structure presented hereinafter to the polymerization reaction at a point in time when a predetermined amount of monomer conversion has occurred.
Inventors
- 👤 William J. Reid
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:44
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/38; C08F14/00; C08F14/02; C08F14/04; C08F14/06
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
86 words
In the process for the suspension polymerization of vinyl chloride monomer which comprises adding the monomer to an aqueous reaction system containing effective amounts of a suspending agent and a polymerization initiator, terminating the polymerization reaction and isolating the polyvinyl chloride, the improvement which comprises terminating the polymerization reaction by the addition to the reaction system at a point within the range of 70 to 95% monomer conversion of 25-5000 ppm, by weight of a vinyl chloride monomer, of a compound corresponding to the formula ##STR16##
Claim 2
Dependent Claim
86 words
In the process for the suspension polymerization of vinyl chloride monomer which comprises adding the monomer to an aqueous reaction system containing effective amounts of a suspending agent and a polymerization initiator, terminating the polymerization reaction and isolating the polyvinyl chloride, the improvement which comprises terminating the polymerization reaction by the addition to the reaction system at a point within the range of 70 to 95% monomer conversion of 25-5000 ppm, by weight of a vinyl chloride monomer, of a compound corresponding to the formula ##STR16##
Claim 3
Dependent Claim
16 words
The process of claim 1, wherein said addition occurs within the range of 70-90% monomer conversion.
Claim 4
Dependent Claim
14 words
The process of claim 2, wherein said addition occurs at about 70% monomer conversion.
Claim 5
Dependent Claim
17 words
The process of claim 3, wherein 50-1000 ppm of said compound are added to the reaction system.
Claim 6
Dependent Claim
17 words
The process of claim 4, wherein 50-500 ppm of said compound are added to the reaction system.
References Cited (Backward Citations)
US3225108A
Cited
US3926910A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-23 | 1988-04-23 | 1988-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-23 | 1992-04-23 | 1992-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-23 | 1996-04-23 | 1996-10-23 | $7700.00 | Window Closed / Lapsed |