Patent US4687814A successfully refreshed from Google Patents.
US4687814A
Expired / Lapsed
US
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Partially hydrophilic, non-ionic crosslinked copolymers and their application to size exclusion chromatography in aqueous media
Assignee: Centre National de la Recherche Scientifique
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Filing: 1985-01-22
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Granted: 1987-08-18
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Expires: 2005-01-22
Abstract
Abstract The invention relates to partially hydrophilic, non-ionic crosslinked copolymers. These copolymers consist of a crosslinked hydrophobic backbone having a high mechanical strength, and of non-ionic hydrophilic chains grafted selectively onto the backbone. The copolymers are useful for size exclusion chromatography in an aqueous medium.
Inventors
- 👤 Philippe Chaumont
- 👤 Gerard Beinert
- 👤 Jean Herz
- 👤 Paul Rempp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:28
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/281; B01J20/291; B01J20/22; B01J20/26; B01J20/261; B01J20/262; B01J20/264; B01J20/265; B01J20/267; B01J20/28; B01J20/28002; B01J20/28011; B01J20/286; B01J20/30; B01J20/3092; B01J20/32; B01J20/3202; B01J20/3206; B01J20/3208; B01J20/321; B01J20/3231; B01J20/3242; B01J20/3268; B01J20/3272; B01J20/3278; C; C08; C08F; C08F8/00; C08G; C08G65/00; C08G65/02; C08G65/04; B01J2220/00; B01J2220/50; B01J2220/54; B01J2220/58
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
58 words
A partially hydrophilic, non-ionic crosslinked copolymer having a three-dimensional network, which consists essentially of a crosslinked hydrophobic backbone of polystyrene having a high mechanical strength and of non-ionic hydrophilic chains of polyoxirane grafted selectively onto said backbone, the grafting of the hydrophilic non-ionic chains onto the hydrophobic backbone of the copolymer being achieved by carbanionic initiation with divinylbenzene.
Claim 2
Dependent Claim
58 words
A partially hydrophilic, non-ionic crosslinked copolymer having a three-dimensional network, which consists essentially of a crosslinked hydrophobic backbone of polystyrene having a high mechanical strength and of non-ionic hydrophilic chains of polyoxirane grafted selectively onto said backbone, the grafting of the hydrophilic non-ionic chains onto the hydrophobic backbone of the copolymer being achieved by carbanionic initiation with divinylbenzene.
Claim 3
Dependent Claim
44 words
A process for the preparation of the copolymer according to claim 1 comprising: (a) crosslinking an α, ω-dicarbanionic polystyrene with divinylbenzene, (b) introducing oxirane into the swollen crosslinked polystyrene and (c) diffusing said oxirane throughout said crosslinked polystyrene and polymerizing said oxirane in situ.
Claim 4
Dependent Claim
31 words
A process according to claim 2, wherein said oxirane is diffused slowly at low temperature and polymerization is effected by increasing the temperature of the reaction medium up to 25° C.
Claim 5
Dependent Claim
19 words
A process according to claim 2, wherein said oxirane is uniformly distributed in the network of the crosslinked polystyrene.
References Cited (Backward Citations)
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GB1429836A
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US3786116A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-17 | 1991-02-16 | 1991-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-17 | 1995-02-16 | 1995-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-17 | 1999-02-16 | 1999-08-18 | $7700.00 | Window Closed / Lapsed |