US5100547A
Expired / Lapsed
US
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Chromatography supports consisting of an inorganic susbstrate coated with polybutadiene with alkyl side chains
Assignee: Monsanto Co
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Filing: 1991-03-04
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Granted: 1992-03-31
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Expires: 2011-03-04
Abstract
Abstract Stationary phases, useful for reversed-phase liquid chromatography, comprise polybutadiene-coated inorganic substrates having enhanced hydrophobicity due to attached alkyl groups, e.g. 2-30 carbon alkyl groups such as an octadecene group, and a low level of carbon-oxygen bonding in the polymer coating, e.g. less than 1 percent of the carbon in the polymer coating is bonded to oxygen.
Inventors
- 👤 Christopher J. Hardiman
- 👤 Jawed Asrar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:16
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/281; B01J20/286; B01J20/287; B01J20/30; B01J20/32; B01J20/3202; B01J20/3204; B01J20/3231; B01J20/3242; B01J20/3268; B01J20/327; B01J20/328; B01J20/3282; B01J2220/00; B01J2220/50; B01J2220/54
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
51 words
A stationary phase for chromatography consisting of an inorganic substrate occludingly-coated with a crosslinked polymer consisting of polybutadiene having attached thereto at least 1 alkyl side chain per 20 olefin monomer units of said polymer and wherein less than 1 percent of the carbon in the polybutadiene is bonded to oxygen.
Claim 2
Dependent Claim
51 words
A stationary phase for chromatography consisting of an inorganic substrate occludingly-coated with a crosslinked polymer consisting of polybutadiene having attached thereto at least 1 alkyl side chain per 20 olefin monomer units of said polymer and wherein less than 1 percent of the carbon in the polybutadiene is bonded to oxygen.
Claim 3
Dependent Claim
39 words
A stationary phase according to claim 1 wherein the substrate is so occludingly coated with said polybutadiene that the integrity of the stationary phase is not adversely affected by extended exposure to liquid environments having a pH of 12.
Claim 4
Dependent Claim
14 words
A stationary phase according to claim 1 wherein said substrate is alumina or silica.
Claim 5
Dependent Claim
24 words
A stationary phase according to claim 3 wherein said substrate has micropores of a diameter predominately in the range of 50 to 1000 Angstroms.
Claim 6
Dependent Claim
33 words
A stationary phase according to claim 4 wherein said substrate comprises a plurality of microporous alumina platelets bonded together to form a macroporous, substantially spherical particle having a nominal diameter of 8 micrometers.
Claim 7
Dependent Claim
20 words
A stationary phase according to claim 1 wherein said alkyl side chains comprise from 2 to about 30 carbon atoms.
Claim 8
Dependent Claim
21 words
A stationary phase according to claim 6 comprising at least 1 alkyl side per 20 olefin monomer units of said polymer.
Claim 9
Dependent Claim
20 words
A stationary phase according to claim 1 wherein substantially all of said alkyl side chains have about 18 carbon atoms.
Claim 10
Dependent Claim
46 words
A stationary phase according to claim 1 wherein the stationary phase exhibits hydrophobicity such that the retention time of o-xylene is increased by at least 15% over retention time for a stationary phase coated with polybutadiene having about 18 mole percent vinyl groups per butadiene unit.
Claim 11
Dependent Claim
17 words
A stationary phase according to claim 9 wherein said retention time is increased by at least 30%.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1995-03-31 | 1995-09-30 | 1996-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-31 | 1999-09-30 | 2000-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-03-31 | 2003-09-30 | 2004-03-31 | $7700.00 | Window Closed / Lapsed |