Patent US3666693A successfully refreshed from Google Patents.
US3666693A
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Sequential graft copolymerization of acid and basic monomers onto a perhalogenated olefin polymer
Assignee: Centre National de la Recherche Scientifique
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Filing: 1969-02-17
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Granted: 1972-05-30
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Expires: 1989-02-17
Abstract
Abstract Improved process of producing semipermeable membranes by graft copolymerization, wherein a perhalogenated olefin polymer substrate has grafted thereonto copolymers having acid and basic groups respectively, where the grafting of acid and basic monomers is carried out sequentially, where the first grafted group is neutralized before the second group is grafted onto the substrate, and where substantially all pendant acid and basic functions are neutralized after grafting has been completed.
Inventors
- 👤 Adolphe Chapiro
- 👤 Anna-Ma Jendrychowska-Bonamour
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 08:02
CPC Classifications
C; C08; C08J; C08J7/00; C08J7/12; C08J7/16; C08J7/18; C08F; C08F259/00; C08F259/08; C08J5/00; C08J5/20; C08J5/22; C08J5/2287; C08J5/2293; C08J2327/00; C08J2327/02; C08J2327/12; C08J2327/18; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31536; Y10T428/3154; Y10T428/31544
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
13 words
A graft copolymer as claimed in claim 1, wherein said substrate is polytetrafluoroethylene.
Claim 2
Dependent Claim
139 words
Process of producing graft copolymers comprising contacting a perhalogenated olefin polymer with one member of the group consisting of olefinically unsaturated copolymerizable carboxylic acids selected from the group consisting of arcylic acid, methacrylic acid and maleic acid and olefinically unsaturated copolymerizable organic bases selected from the group consisting of 4-vinyl pyridine, 2-vinyl pyridine, methyl vinyl pyridine, p-amino styrene, o-amino styrene and amino vinyl toluene; subjecting such to ionizing radiation in an amount and for a time sufficient to graft copolymerize said group member onto said substrate; neutralizing the functionality of said graft copolymer, contacting the neutralized graft copolymer with the other member of said group; subjecting such to ionizing radiation in an amount and for a time sufficient to graft copolymerize said other member onto said graft copolymerized substrate: and neutralizing the functionality of said other graft copolymerized member.
Claim 3
Dependent Claim
20 words
Process claimed in claim 3 wherein said acid is first graft copolymerized and said acid is neutralized with a base.
Claim 4
Dependent Claim
20 words
Process claimed in claim 3 wherein said base is first graft copolymerized and said base is neutralized with an acid.
Claim 5
Dependent Claim
12 words
A semipermeable membrane made of the graft copolymer claimed in claim 1.
References Cited (Backward Citations)
GB1043008A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-30 | 1975-11-29 | 1976-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-30 | 1979-11-29 | 1980-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-30 | 1983-11-29 | 1984-05-30 | $7700.00 | Window Closed / Lapsed |