US3622553A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Agitated reactor and gas fluidized bed reactor in series for polymerization of vinyl chloride
Assignee: Phillips Petroleum Co
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Filing: 1967-12-18
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Granted: 1971-11-23
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Expires: 1987-12-18
Abstract
Abstract Vinyl chloride, alone or with a suitable comonomer, is continuously polymerized under liquid phase bulk conditions in an agitated reactor to a solid polymer content about 15 percent. A portion of the reaction effluent is continuously or periodically withdrawn from the agitated reactor and flushed into a fluidized bed reactor wherein vaporous vinyl chloride is employed as the fluidizing gas. Vinyl chloride gas is withdrawn and at least a portion thereof reintroduced into the fluidized reactor as the fluidizing gas. The excess vinyl chloride gas can be condensed and recycled to the agitated reactor. A polymer stream is withdrawn and passed through a monomer recovery system which can include a wash tower, a flash tank, drying conveyors and inert gas and/or vacuum strippers.
Inventors
- 👤 Martin R Cines
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 04:18
CPC Classifications
C; C08; C08F; C08F14/00; C08F14/02; C08F14/04; C08F14/06; Y; Y10; Y10S; Y10S526/00; Y10S526/921
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
297 words
A continuous process for the polymerization of monomer selected from the group consisting of vinyl chloride and combinations of vinyl chloride with at least one suitable comonomer, the vinyl chloride constituting at least 60 weight percent of the total comonomers, which comprises at least substantially continuousLy introducing said monomer in the liquid phase into a first polymerization zone, at least substantially continuously introducing a suitable polymerization catalyst into said first polymerization zone, maintaining said first polymerization zone under polymerization conditions at which said monomer is in the liquid phase, agitating the resulting mixture of monomer, catalyst and solid polymer particles in said first polymerization zone, at least substantially continuously withdrawing from said first polymerization zone a portion of said mixture to maintain the concentration of polymer in said mixture in said first polymerization zone at less than 15 weight percent, maintaining a second polymerization zone under polymerization conditions at which the unabsorbed monomer contained therein is in the gaseous state, introducing into said second polymerization zone the thus withdrawn portion of said mixture to vaporize the unabsorbed part of the monomer contained in said withdrawn portion while leaving monomer absorbed in the solid polymer particles, continuously passing a stream of said monomer in the gaseous state upwardly through said second polymerization zone to maintain a fluidized bed of solid polymer particles, at least substantially continuously withdrawing from a lower portion of said second polymerization zone solid polymer particles at least substantially free of absorbed monomer, continuously withdrawing gaseous monomer from an upper portion of said second polymerization zone, compressing the thus withdrawn gaseous monomer, and passing at least a portion of the thus compressed gaseous monomer to the step of continuously passing a stream of said monomer in the gaseous state upwardly through said second polymerization zone.
Claim 2
Dependent Claim
297 words
A continuous process for the polymerization of monomer selected from the group consisting of vinyl chloride and combinations of vinyl chloride with at least one suitable comonomer, the vinyl chloride constituting at least 60 weight percent of the total comonomers, which comprises at least substantially continuousLy introducing said monomer in the liquid phase into a first polymerization zone, at least substantially continuously introducing a suitable polymerization catalyst into said first polymerization zone, maintaining said first polymerization zone under polymerization conditions at which said monomer is in the liquid phase, agitating the resulting mixture of monomer, catalyst and solid polymer particles in said first polymerization zone, at least substantially continuously withdrawing from said first polymerization zone a portion of said mixture to maintain the concentration of polymer in said mixture in said first polymerization zone at less than 15 weight percent, maintaining a second polymerization zone under polymerization conditions at which the unabsorbed monomer contained therein is in the gaseous state, introducing into said second polymerization zone the thus withdrawn portion of said mixture to vaporize the unabsorbed part of the monomer contained in said withdrawn portion while leaving monomer absorbed in the solid polymer particles, continuously passing a stream of said monomer in the gaseous state upwardly through said second polymerization zone to maintain a fluidized bed of solid polymer particles, at least substantially continuously withdrawing from a lower portion of said second polymerization zone solid polymer particles at least substantially free of absorbed monomer, continuously withdrawing gaseous monomer from an upper portion of said second polymerization zone, compressing the thus withdrawn gaseous monomer, and passing at least a portion of the thus compressed gaseous monomer to the step of continuously passing a stream of said monomer in the gaseous state upwardly through said second polymerization zone.
Claim 3
Dependent Claim
34 words
A process in accordance with claim 1 wherein the remaining portion of said compressed gaseous monomer is condensed and passed to said first polymerization zone as a portion of the liquid monomer feed thereto.
Claim 4
Dependent Claim
50 words
A process in accordance with claim 1 wherein said portion of the thus compressed gaseous monomer is passed through an indirect heat exchange zone to vary the temperature of the gaseous monomer utilized to fluidize the bed of solid polymer particles to thereby control the temperature of said fluidized bed.
Claim 5
Dependent Claim
50 words
A process in accordance with claim 1 wherein said mixture being substantially free of solvent, said catalyst is a free radical precursor, and said portion of said mixture is substantially continuously withdrawn from said first polymerization zone to maintain the polymer concentration in said mixture less than 10 weight percent.
Claim 6
Dependent Claim
13 words
A process in accordance with claim 1 wherein said monomer is vinyl chloride.
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) | 1974-11-22 | 1975-05-24 | 1975-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-22 | 1979-05-24 | 1979-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-22 | 1983-05-24 | 1983-11-23 | $7700.00 | Window Closed / Lapsed |