Patent US4093787A successfully refreshed from Google Patents.
US4093787A
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Vinyl chloride polymerization process
Assignee: European Vinyls Corp Technology AG
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Filing: 1975-08-14
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Granted: 1978-06-06
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Expires: 1995-08-14
Abstract
Abstract Vinyl chloride is polymerized in aqueous dispersion, preferably in aqueous dispersion, preferably in aqueous suspension, in a reactor with walls coated with a layer of a cross-linked polymeric material containing polar groups formed from a reaction mixture having an aldehyde, preferably formaldehyde, as one component thereof.
Inventors
- 👤 Robin Henry Burgess
- 👤 Jeffrey Chester Greaves
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:11
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/002; C08F2/004
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
71 words
A process for the production of vinyl chloride polymers which comprises polymerizing vinyl chloride, or vinyl chloride and up to 20% by weight thereof of at least one ethylenically unsaturated monomer copolymerizable therewith, an aqueous dispersion, in a reactor having an inner wall(s) on which there has been directly deposited an insoluble layer of a cross-linked polymeric material containing polar groups and comprising a reaction product of formaldehyde and polyethylene imine.
Claim 2
Dependent Claim
71 words
A process for the production of vinyl chloride polymers which comprises polymerizing vinyl chloride, or vinyl chloride and up to 20% by weight thereof of at least one ethylenically unsaturated monomer copolymerizable therewith, an aqueous dispersion, in a reactor having an inner wall(s) on which there has been directly deposited an insoluble layer of a cross-linked polymeric material containing polar groups and comprising a reaction product of formaldehyde and polyethylene imine.
Claim 3
Dependent Claim
19 words
A process according to claim 1 in which the polymerisation medium is maintained at a pH greater than 4.
Claim 4
Dependent Claim
11 words
A process according to claim 1 which is a batch polymerisation.
Claim 5
Dependent Claim
16 words
A process according to claim 1 in which the polymerisation is carried out in aqueous suspension.
Claim 6
Dependent Claim
56 words
A process according to claim 1 in which the layer of cross-linked polymer material is formed by applying a solution or dispersion of each component from which the material is formed separately or in admixture with one or more of the other components to the reactor wall and allowing the components to react on the wall.
Claim 7
Dependent Claim
43 words
A process according to claim 1 which is batch polymerisation and in which the amount of cross-linked polymeric material used is within the range of 1 to 2,000 parts per million, based on the weight of the vinyl chloride used in the polymerisation.
Claim 8
Dependent Claim
25 words
A process according to claim 1 in which the amount of cross-linked polymeric material used lies within the range 10 to 200 parts per million.
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) | 1981-06-05 | 1981-12-05 | 1982-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-05 | 1985-12-05 | 1986-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-05 | 1989-12-05 | 1990-06-06 | $7700.00 | Window Closed / Lapsed |