Patent DE1028839B successfully refreshed from Google Patents.
US4032440A
Expired / Lapsed
US
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Semipermeable membrane
Assignee: United States Department of the Interior
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Filing: 1975-11-18
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Granted: 1977-06-28
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Expires: 1995-11-18
Abstract
Abstract A semipermeable composite membrane is prepared by glow discharge polymerization of a combination of an organic monomer and an inorganic monomer in the presence of a porous support, the polymerization resulting in deposition of a thin film of copolymer on the surface of the support.
Inventors
- 👤 Hirotsugu Yasuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:07
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/12; B01D69/125; B01D69/127
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
111 words
A process for preparation of a composite semipermeable membrane comprising: (1) positioning a porous support in an atmosphere comprising a polymerizable admixture of (a) an organic monomer from the group consisting of acetylene, ethylene, allene, benzene, pyridine and furfurylamine and (b) an inorganic monomer consisting of water or a mixture of water with nitrogen or carbon monoxide, said admixture being in vapor form, and (2) subjecting said admixture to the influence of electromagnetic energy of a frequency of about 50 Hz to 3000 mHz to produce an electric glow discharge, thereby causing copolymerization of the monomers and deposition of the resulting copolymer as a film on the surface of the support.
Claim 2
Dependent Claim
111 words
A process for preparation of a composite semipermeable membrane comprising: (1) positioning a porous support in an atmosphere comprising a polymerizable admixture of (a) an organic monomer from the group consisting of acetylene, ethylene, allene, benzene, pyridine and furfurylamine and (b) an inorganic monomer consisting of water or a mixture of water with nitrogen or carbon monoxide, said admixture being in vapor form, and (2) subjecting said admixture to the influence of electromagnetic energy of a frequency of about 50 Hz to 3000 mHz to produce an electric glow discharge, thereby causing copolymerization of the monomers and deposition of the resulting copolymer as a film on the surface of the support.
Claim 3
Dependent Claim
16 words
The process of claim 1 in which the porous support consists of an organic polymeric material.
Claim 4
Dependent Claim
21 words
The process of claim 2 in which the organic polymeric material is a mixed polymer of cellulose acetate and cellulose nitrate.
Claim 5
Dependent Claim
13 words
The process of claim 2 in which the organic polymeric material is polysulfone.
Claim 6
Dependent Claim
12 words
The process of claim 1 in which the organic monomer is acetylene.
Claim 7
Dependent Claim
12 words
The process of claim 1 in which the organic monomer is ethylene.
Claim 8
Dependent Claim
12 words
The process of claim 1 in which the organic monomer is allene.
Claim 9
Dependent Claim
12 words
The process of claim 1 in which the organic monomer is benzene.
Claim 10
Dependent Claim
12 words
The process of claim 1 in which the organic monomer is pyridine.
Claim 11
Dependent Claim
12 words
The process of claim 1 in which the organic monomer is furfurylamine.
Claim 12
Dependent Claim
12 words
The process of claim 1 in which the inorganic monomer is water.
Claim 13
Dependent Claim
23 words
The process of claim 1 in which the electromagnetic energy has a frequency in the range of about 50 Hz to 1000 mHz.
Claim 14
Dependent Claim
11 words
A composite semipermeable membrane prepared by the process of claim 1.
Claim 15
Dependent Claim
38 words
In a process for desalination of saline water by reverse osmosis comprising contacting the saline water under pressure with a reverse osmosis membrane, the improvement comprising using the composite membrane of claim 13 as the reverse osmosis membrane.
References Cited (Backward Citations)
US3775308A
Cited
US3847652A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-06-27 | 1980-12-27 | 1981-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-27 | 1984-12-27 | 1985-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-27 | 1988-12-27 | 1989-06-28 | $7700.00 | Window Closed / Lapsed |