US4439217A
Expired / Lapsed
US
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Permselective element for gas separation
Assignee: AGC Inc
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Filing: 1982-11-05
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Granted: 1984-03-27
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Expires: 2002-11-05
Abstract
Abstract A permselective element for gas separation comprises a permselective layer composed of an organic polymer having -OCOC(CH3)3 groups in its side chains. The permselective element is useful for the separation of oxygen/nitrogen.
Inventors
- 👤 Masaaki Yamabe
- 👤 Katsuyuki Akiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:37
CPC Classifications
C; C01; C01B; C01B13/00; C01B13/02; C01B13/0229; C01B13/0248; C01B13/0251; C01B13/0255; B; B01; B01D; B01D71/00; B01D71/06; B01D71/76; B01D71/82; C01B2210/00; C01B2210/0043; C01B2210/0046
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
26 words
A permselective element for gas separation which comprises a permselective layer composed of an organic polymer having --OCOC(CH 3 ) 3 groups in its side chains.
Claim 2
Dependent Claim
26 words
A permselective element for gas separation which comprises a permselective layer composed of an organic polymer having --OCOC(CH 3 ) 3 groups in its side chains.
Claim 3
Dependent Claim
14 words
The permselective element according to claim 1 wherein the organic polymer is polyvinyl pivalate.
Claim 4
Dependent Claim
20 words
The permselective element according to claim 1 wherein the organic polymer is a copolymer of vinyl pivalate with other comonomer.
Claim 5
Dependent Claim
24 words
The permselective element according to claim 3 wherein the proportion of the vinyl pivalate units in the copolymer is at least 5 molar %.
Claim 6
Dependent Claim
19 words
The permselective element according to claim 1 wherein the organic polymer is the one formed by a polymer reaction.
Claim 7
Dependent Claim
21 words
The permselective element according to claim 5 wherein the polymer reaction is pivalic acid esterification of a polymer containing hydroxyl groups.
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) | 1987-03-27 | 1987-09-26 | 1988-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-03-27 | 1991-09-26 | 1992-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-03-27 | 1995-09-26 | 1996-03-27 | $7700.00 | Window Closed / Lapsed |