Patent US4267291A successfully refreshed from Google Patents.
US4267291A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for coating reactors using organic compound vapor application
Assignee: Geon Co
•
Filing: 1979-09-14
•
Granted: 1981-05-12
•
Expires: 1999-09-14
Abstract
Abstract This invention relates to the reduction of polymer buildup on the inner surfaces of a polymerization reactor by applying a polymer buildup resistant coating to the inner surfaces thereof, the method or process of applying said coating being the subject of this invention. An approximate monolayer coating on the inner surfaces of the reactor results from applying thereto an aqueous or organic solvent solution of the coating material by means of a hydrocarbon gas, such as propane, for example. The coating material is an organic compound or polymer which is capable of resisting polymer buildup thereon. As examples of such coating materials, there may be named the polyaromatic amines, self-condensed polyhydric phenols, tannic acid and tannates, various dyes, such as nigrosine, and the like, etc. When using hydrocarbon gas to apply the coating material, the same reaches the inner reactor surfaces in the form of a mist. When polymerizing olefinic monomers, such as vinyl halides, vinylidene halides, and vinylidene monomers having at least one terminal CH 2 ═C< grouping, and mixtures thereof, in the presence of said coating, polymer buildup on the inner surfaces of said reactor is substantially eliminated.
Inventors
- 👤 Richard A. Jones
- 👤 Donald E. Witenhafer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:26
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/002; C08F2/004; B; B08; B08B; B08B17/00; B08B17/02
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
106 words
A process for substantially eliminating the buildup of polymer on the internal surfaces of a polymerization reaction vessel for polymerizing olefinic monomer(s) which comprises, making a coating solution of a coating material which, in the form of a film, is capable of resisting polymer buildup thereon, applying said coating material to said surfaces by means of a hydrocarbon gas, said hydrocarbon gas being a saturated straight chain or branched hydrocarbon containing from 1 to 8 carbon atoms and acting as a carrier for said coating material, and thereafter conducting the polymerization of said monomer(s) while in constant contact with the coated internal surfaces of said vessel.
Claim 2
Dependent Claim
106 words
A process for substantially eliminating the buildup of polymer on the internal surfaces of a polymerization reaction vessel for polymerizing olefinic monomer(s) which comprises, making a coating solution of a coating material which, in the form of a film, is capable of resisting polymer buildup thereon, applying said coating material to said surfaces by means of a hydrocarbon gas, said hydrocarbon gas being a saturated straight chain or branched hydrocarbon containing from 1 to 8 carbon atoms and acting as a carrier for said coating material, and thereafter conducting the polymerization of said monomer(s) while in constant contact with the coated internal surfaces of said vessel.
Claim 3
Dependent Claim
13 words
A process as defined in claim 1 wherein the monomer is vinyl chloride.
Claim 4
Dependent Claim
31 words
A process as defined in claim 1 wherein the coating material is present in said coating solution in an amount in the range of about 0.001% to about 20.0% by weight.
Claim 5
Dependent Claim
41 words
A process as defined in claim 1 wherein the temperature of the hydrocarbon gas is in the range of about 20° C. to about 100° C. and said hydrocarbon gas under a pressure of about 20 psig to about 1000 psig.
Claim 6
Dependent Claim
49 words
A process as defined in claim 1 wherein the coating material is a polyaromatic amine made by the condensation reaction of any one by itself or more than one of the compounds selected from the group consisting of polyamino benzenes, polyhydric phenols, aminophenols, alkyl-substituted aminophenols, diphenylamines, and alkyl-substituted diphenylamines.
Claim 7
Dependent Claim
20 words
A process as defined in claim 5 wherein the coating solution is an organic solvent solution of the polyaromatic amine.
Claim 8
Dependent Claim
22 words
A process as defined in claim 5 wherein the coating solution is an aqueous alkali metal hydroxide solution of the polyaromatic amine.
Claim 9
Dependent Claim
37 words
A process as defined in claim 7 wherein the coating solution contains a dispersant operable in aqueous media and selected from the group consisting of polyvinyl alcohol, polyvinyl pyrrolidone, gelatin (calf skin), starch, and hydroxypropyl methyl cellulose.
Claim 10
Dependent Claim
64 words
A process as defined in claim 1 wherein the coating solution is comprised of an aqueous alkali metal hydroxide solution containing a condensation product selected from the group consisting of the self-condensation product of one or more polyhydric phenols, and the self-condensation product of a polyhydric naphthol, and wherein said polyhydric phenol(s) is selected from the group consisting of resorcinol, hydroquinone, catechol and phloroglucinol.
Claim 11
Dependent Claim
41 words
A process as defined in claim 1 wherein the coating solution is comprised of an aqueous solution of a tannin, said tannin being selected from the group consisting of hydrolyzable tannins, condensed tannins, ammonium tannates, and tannins complexed with metal ions.
Claim 12
Dependent Claim
13 words
A process as defined in claim 10 wherein the monomer is vinyl chloride.
Claim 13
Dependent Claim
50 words
A process as defined in claim 1 wherein the coating solution is comprised of an aqueous alkali metal hydroxide solution of an alkalisoluble dye, said dye having one or more radicals in its chemical structure selected from the group consisting of --OH, --COOH, --SO 3 H, and --SO 3 Na.
Claim 14
Dependent Claim
25 words
A process as defined in claim 12 wherein the dye is an ionic dye selected from the group consisting of acridines, azines, oxazines, and thiazines.
Claim 15
Dependent Claim
23 words
A process as defined in claim 1 wherein the coating solution is comprised of an organic solvent solution of an organic solvent-soluble dye.
Claim 16
Dependent Claim
18 words
A process as defined in claim 14 wherein the dye is nigrosine and the solvent is dimethyl formamide.
Claim 17
Dependent Claim
47 words
A process as defined in claim 1 wherein the coating solution is comprised of an aqueous solution of a water-soluble dye, said dye having one or more radicals in its chemical structure selected from the group consisting of --COONa, --COOH, --SO 3 H and --SO 3 Na.
Claim 18
Dependent Claim
16 words
A process as defined in claim 1 wherein the monomers are vinyl chloride and vinyl acetate.
Claim 19
Dependent Claim
13 words
A process as defined in claim 1 wherein the hydrocarbon gas is propane.
Claim 20
Dependent Claim
13 words
A process as defined in claim 18 wherein the monomer is vinyl chloride.
References Cited (Backward Citations)
US3669946A
Cited
US4024330A
Cited
US4024301A
Cited
US4081248A
Cited
US4068059A
Cited
US4080173A
Cited
US4105840A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-05-11 | 1984-11-10 | 1985-05-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-05-11 | 1988-11-10 | 1989-05-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-05-11 | 1992-11-10 | 1993-05-12 | $7700.00 | Window Closed / Lapsed |