US4861628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thin film composite membrane prepared by suspension deposition
Assignee: ExxonMobil Technology and Engineering Co
•
Filing: 1987-10-14
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Granted: 1989-08-29
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Expires: 2007-10-14
Abstract
Abstract Thin film membranes of polyurea, polyureapolyurethane alloy, polyurea-polyurea/urethane alloy or polyurea/urethane are prepared by deposition of a thin film of suspension of the selected polymer on a thick permeable support layer by the technique of preparing a suspension of the selected polymer in a solvent which does not dissolve the thick permeable support layer and permitting the solvent to evaporate and/or permeate through the thick-permeable layer.
Inventors
- 👤 Robert C. Schucker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:05
CPC Classifications
B; B01; B01D; B01D61/00; B01D61/24; B01D61/246; B01D61/36; B01D61/362; B01D63/00; B01D63/02; B01D67/00; B01D67/0039; B01D67/0048; B01D69/00; B01D69/08; B01D69/10; B01D69/107; B01D69/12; B01D69/1213; B01D69/125; B01D71/00; B01D71/06; B01D71/54; C; C08; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/10; C08G18/28; C08G18/30; C08G18/32; C08G18/3225; C08G18/3237; C08G18/3243; C10; C10G; C10G31/00; C10G31/11; B01D2323/00; B01D2323/12; Y; Y10; Y10S; Y10S264/00; Y10S264/18
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
133 words
A method for producing thin film composite membranes for separating aromatic hydrocarbons from non-aromatic hydrocarbons, consisting of a thin active layer of polymer, selected from polyurea/urethane copolymer, polyurea, polyurea-polyurethane alloy, or a polyurea-polyurea/urethane alloy on a porous support layer by synthesizing the polymer in a dispersing solvent thereby producing a dispersion-suspension of the polymer in the dispersing solvent which does not dissolve the porous support layer, the polymer being present in the dispersion-suspension at a concentration of from about 0.5 to about 10% polymer, depositing a layer of the dispersion-suspension on one face of the porous support layer, and permitting the dispersing solvent to either evaporate from the dispersion-suspension layer or permeate through the porous support layer, thereby depositing the thin film of a thickness 2 microns or less on the support layer.
Claim 2
Independent Claim
133 words
A method for producing thin film composite membranes for separating aromatic hydrocarbons from non-aromatic hydrocarbons, consisting of a thin active layer of polymer, selected from polyurea/urethane copolymer, polyurea, polyurea-polyurethane alloy, or a polyurea-polyurea/urethane alloy on a porous support layer by synthesizing the polymer in a dispersing solvent thereby producing a dispersion-suspension of the polymer in the dispersing solvent which does not dissolve the porous support layer, the polymer being present in the dispersion-suspension at a concentration of from about 0.5 to about 10% polymer, depositing a layer of the dispersion-suspension on one face of the porous support layer, and permitting the dispersing solvent to either evaporate from the dispersion-suspension layer or permeate through the porous support layer, thereby depositing the thin film of a thickness 2 microns or less on the support layer.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein the dispersion solvent is selected from 1,4-dioxane, cellosolve acetate, ttrahydrofuran, ketones and aromatic hydrocarbons.
Claim 4
Dependent Claim
22 words
The method of claim 2 wherein the porous support layer is selected from polyamide, polyimide, polyacrylonitrile, polybenzimidazole, cellulose acetate, tefton, and polyolefins.
Claim 5
Dependent Claim
76 words
The method of claim 1 wherein the polyurea/urethane copolymer thin active layer of the thin film composite membrane is characterized by possessing a urea index of at least about 20% but less than 100%, an aromatic carbon content of at least about 15 mole percent, a functional group density defined as the total of C═O and NH per 1000 grams of polymer is greater than about 10 and a C═O/NH ratio of less than about 8.
Claim 6
Dependent Claim
31 words
The method of claim 1 wherein the polyurea thin active layer of the thin film composite membrane is characterized by possessing a total aromatic carbon content of about 86% or less.
Claim 7
Dependent Claim
29 words
The method of claim 1 wherein the polyurea-polyurethane alloy thin active layer of the thin film composite membrane is characterized by possessing about 5 to 95 wt % polyurea.
Claim 8
Dependent Claim
99 words
The method of claim 1 wherein the polyurea-polyurea/urethane alloy thin active layer of the thin film composite membrane is characterized by possessing a ratio of polyurea polymer to polyurea/urethane copolymer in the range of 10 to 90 and the polyurea/urethane copolymer is characterized by possessing a urea index of at least about 20% but less than 100%, an aromatic carbon content of at least about 15 mole percent, a functional group density defined as the total of C═O and NH per 1000 grams of polymer is greater than about 10 and a C═O/NH ratio of less than about 8.
References Cited (Backward Citations)
DE151952C
Cited
DE150620C
Cited
DE151874C
Cited
US2930754A
Cited
US2958656A
Cited
US2947687A
Cited
US2970106A
Cited
US3456037A
Cited
US3595732A
Cited
US3715326A
Cited
US3370102A
Cited
US3567810A
Cited
US3762566A
Cited
GB1391559A
Cited
US3776970A
Cited
US4129559A
Cited
US3876738A
Cited
US4036748A
Cited
US4230583A
Cited
US4115465A
Cited
US4340479A
Cited
US4340479B1
Cited
US4374232A
Cited
US4774039A
Cited
US4389494A
Cited
EP0050789A1
Cited
US4421579A
Cited
GB2115344A
Cited
US4532316A
Cited
DE3513980A1
Cited
JPS6436337A
Cited
JPH07239079A
Cited
JPH0887115A
Cited
JPH0892418A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-28 | 1993-02-27 | 1993-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-28 | 1997-02-27 | 1997-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-28 | 2001-02-27 | 2001-08-29 | $7700.00 | Window Closed / Lapsed |