US4007320A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for reducing polymer build-up
Assignee: Norsk Hydro ASA
•
Filing: 1975-04-29
•
Granted: 1977-02-08
•
Expires: 1995-04-29
Abstract
Abstract The present invention relates to a process for reducing the build-up of polymer on the internal surfaces of a polymerization vessel. This is accomplished according to the invention by coating the internal surfaces of the polymerization vessel with a polymeric material and insolubilizing said material by cross-linking.
Inventors
- 👤 Jorgen Petersen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:16
CPC Classifications
B; B05; B05D; B05D7/00; B05D7/22; C; C08; C08F; C08F2/00; C08F2/002; C08F2/004
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
57 words
A process for reducing the build-up of polymer on the internal surfaces of a reaction vessel for polymerization of ethylenically unsaturated polymerizable compounds in aqueous dispersion which comprises the steps of a. coating major parts of said surfaces with a polymeric material containing hydroxy groups, and b. insolubilizing said polymeric material by cross-linking with an organic titanate.
Claim 2
Dependent Claim
57 words
A process for reducing the build-up of polymer on the internal surfaces of a reaction vessel for polymerization of ethylenically unsaturated polymerizable compounds in aqueous dispersion which comprises the steps of a. coating major parts of said surfaces with a polymeric material containing hydroxy groups, and b. insolubilizing said polymeric material by cross-linking with an organic titanate.
Claim 3
Dependent Claim
15 words
A process according to claim 1, characterized in that the polymeric material is polyvinyl alcohol.
Claim 4
Dependent Claim
14 words
A process according to claim 1, characterized in that the polymeric material is starch.
Claim 5
Dependent Claim
16 words
A process according to claim 1, characterized in that the organic titanate is a titanium chelate.
Claim 6
Dependent Claim
81 words
A process for the polymerization of vinyl chloride or styrene or a mixture of vinyl chloride or styrene and at least one other unsaturated copolymerizable compound in an amount of up to 20 percent by weight based on the amount of vinyl chloride or styrene, wherein the polymerization is conducted in a polymerization vessel where major parts of the internal surfaces have been coated with a polymeric material containing hydroxy groups which has been insolubilized by cross-linking with an organic titanate.
Claim 7
Dependent Claim
81 words
A process for the polymerization of vinyl chloride or styrene or a mixture of vinyl chloride or styrene and at least one other unsaturated copolymerizable compound in an amount of up to 20 percent by weight based on the amount of vinyl chloride or styrene, wherein the polymerization is conducted in a polymerization vessel where major parts of the internal surfaces have been coated with a polymeric material containing hydroxy groups which has been insolubilized by cross-linking with an organic titanate.
Claim 8
Dependent Claim
15 words
A process according to claim 5, characterized in that the polymeric material is polyvinyl alcohol.
Claim 9
Dependent Claim
14 words
A process according to claim 5, characterized in that the polymeric material is starch.
Claim 10
Dependent Claim
16 words
A process according to claim 5, characterized in that the organic titanate is a titanium chelate.
Claim 11
Dependent Claim
34 words
A polymerization reaction vessel having on major parts of its internal surfaces a coating of a polymeric material containing hydroxy groups insolubilized by cross-linking with an organic titanate, whereby polymer build-up is substantially reduced.
Claim 12
Dependent Claim
34 words
A polymerization reaction vessel having on major parts of its internal surfaces a coating of a polymeric material containing hydroxy groups insolubilized by cross-linking with an organic titanate, whereby polymer build-up is substantially reduced.
References Cited (Backward Citations)
US3515709A
Cited
US3669946A
Cited
US3778423A
Cited
US3804924A
Cited
DE2357869A1
Cited
US3849179A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-08 | 1980-08-09 | 1981-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-08 | 1984-08-09 | 1985-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-08 | 1988-08-09 | 1989-02-08 | $7700.00 | Window Closed / Lapsed |