US4205149A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of removing vinyl chloride monomer from polyvinyl chloride resins
Assignee: Geon Co
•
Filing: 1974-12-23
•
Granted: 1980-05-27
•
Expires: 1994-12-23
Abstract
Abstract This invention relates to a method for the removal of vinyl chloride monomer from polyvinyl chloride resins by lowering the Tg (glass transition temperature) of the polyvinyl chloride resins at an elevated temperature while in the presence of reduced pressure thus allowing the vinyl chloride monomer to escape from the polyvinyl chloride resins.
Inventors
- 👤 Frank A. Cich
- 👤 Emmett J. Glazer
- 👤 Edwin S. Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:49
CPC Classifications
C; C08; C08F; C08F6/00; C08F6/001
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
46 words
The method which comprises polymerizing monomeric vinyl chloride in an emulsion or suspension polymerization system to form vinyl chloride polymer in the presence of propane and reducing the pressure in the system to remove substantially all of the unreacted vinyl chloride and propane from the system.
Claim 2
Independent Claim
46 words
The method which comprises polymerizing monomeric vinyl chloride in an emulsion or suspension polymerization system to form vinyl chloride polymer in the presence of propane and reducing the pressure in the system to remove substantially all of the unreacted vinyl chloride and propane from the system.
Claim 3
Independent Claim
47 words
The method which comprises polymerizing monomeric vinyl chloride in an emulsion or suspension polymerization system to form polymeric vinyl chloride, adding propane to the system and then reducing the pressure in the system to remove substantially all of the unreacted vinyl chloride and propane from the system.
Claim 4
Independent Claim
47 words
The method which comprises polymerizing monomeric vinyl chloride in an emulsion or suspension polymerization system to form polymeric vinyl chloride, adding propane to the system and then reducing the pressure in the system to remove substantially all of the unreacted vinyl chloride and propane from the system.
Claim 5
Independent Claim
58 words
The method which comprises polymerizing monomeric vinyl chloride in a bulk polymerization system to form polymeric vinyl chloride in the presence of butane and reducing the pressure in the system to remove substantially all of the unreacted vinyl chloride monomer and butane from the system and recovering the polymeric vinyl chloride formed substantially free of monomeric vinyl chloride.
Claim 6
Independent Claim
58 words
The method which comprises polymerizing monomeric vinyl chloride in a bulk polymerization system to form polymeric vinyl chloride in the presence of butane and reducing the pressure in the system to remove substantially all of the unreacted vinyl chloride monomer and butane from the system and recovering the polymeric vinyl chloride formed substantially free of monomeric vinyl chloride.
Claim 7
Independent Claim
58 words
The method which comprises polymerizing vinyl chloride in a bulk polymerization system to form polymeric vinyl chloride, adding butane to the system and then reducing the pressure in the system to remove substantially all of the unreacted vinyl chloride monomer and butane from the system and recovering the polymeric vinyl chloride formed substantially free of monomeric vinyl chloride.
Claim 8
Independent Claim
58 words
The method which comprises polymerizing vinyl chloride in a bulk polymerization system to form polymeric vinyl chloride, adding butane to the system and then reducing the pressure in the system to remove substantially all of the unreacted vinyl chloride monomer and butane from the system and recovering the polymeric vinyl chloride formed substantially free of monomeric vinyl chloride.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-05-27 | 1983-11-26 | 1984-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-05-27 | 1987-11-26 | 1988-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-05-27 | 1991-11-26 | 1992-05-27 | $7700.00 | Window Closed / Lapsed |