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US4973607A
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Cation exchange resins incorporating antioxidants
Assignee: Dow Chemical Co
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Filing: 1988-09-23
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Granted: 1990-11-27
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Expires: 2008-09-23
Abstract
Abstract Cation exchange resins with improved stability prepared by treating the resins with an antioxidant are disclosed.
Inventors
- 👤 James R. Stahlbush
- 👤 Robert M. Strom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:42
CPC Classifications
B; B01; B01J; B01J47/00; B01J47/016
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
67 words
A method of improving the stability of a cation exchange resin made from vinyl monomers which comprises contacting the cation exchange resin with at least 0.01 weight percent organic antioxidant, and the cation exchange resin releases lower amounts of decomposition products as compared to a cation exchange resin not treated with the antioxidant, and wherein said cation exchange resin contains no antioxidants bonded to said resin backbone.
Claim 2
Independent Claim
67 words
A method of improving the stability of a cation exchange resin made from vinyl monomers which comprises contacting the cation exchange resin with at least 0.01 weight percent organic antioxidant, and the cation exchange resin releases lower amounts of decomposition products as compared to a cation exchange resin not treated with the antioxidant, and wherein said cation exchange resin contains no antioxidants bonded to said resin backbone.
Claim 3
Dependent Claim
31 words
The method of claim 1 wherein the antioxidant is a monocyclic or polycyclic phenol, an amine, a diamine, a thioester, a phosphite, a quinoline, or a mixture of any of these.
Claim 4
Dependent Claim
14 words
The method of claim 2 wherein the antioxidant is a monocyclic or polycyclic phenol.
Claim 5
Dependent Claim
12 words
The method of claim 3 wherein the antioxidant is a monocyclic phenol.
Claim 6
Dependent Claim
17 words
The method of claim 4 wherein the monocyclic phenol is a substituted monohydroxy, dihydroxy or trihydroxy benzene.
Claim 7
Dependent Claim
12 words
The method of claim 5 wherein the trihydroxy benzene is n-propyl gallate.
Claim 8
Dependent Claim
11 words
The method of claim 5 wherein the dihydroxy benzene is t-butylhydroquinone.
Claim 9
Dependent Claim
13 words
The method of claim 5 wherein the monocyclic phenol is a monohydroxy benzene.
Claim 10
Dependent Claim
11 words
The method of claim 8 wherein the monohydroxy benzene is 3-t-butyl-4-methoxyphenol.
Claim 11
Dependent Claim
27 words
The method of claim 8 wherein the monohydroxy benzene is substituted with one or more t-butyl groups on at least one position ortho to the hydroxy group.
Claim 12
Dependent Claim
22 words
The method of claim 10 wherein the monohydroxy benzene is substituted with t-butyl groups on each position ortho to the hydroxy group.
Claim 13
Dependent Claim
15 words
The method of claim 11 wherein the phenol is BHT, 2-t-butyl-4-methoxyphenol, 2,6-di-t-butyl-α-ethylamino-p-cresol, or calcium bis(0-ethyl-(3,5-di-t-butyl-4-hydroxybenzyl)phosphonate).
Claim 14
Dependent Claim
12 words
The method of claim 12 wherein the phenol is BHT or 2,6-di-t-butyl-α-dimethylamino-p-cresol.
Claim 15
Dependent Claim
25 words
The method of claim 1 wherein the amount of the antioxidant incorporated into the resin is from about 0.001 to about 10 percent by weight.
Claim 16
Dependent Claim
25 words
The method of claim 14 wherein the amount of the antioxidant incorporated into the resin is from about 0.01 to about 0.5 percent by weight.
Claim 17
Dependent Claim
23 words
The method for claim 1 wherein the resin has a crosslinked copolymer matrix of a monovinyl aromatic monomer and a divinyl aromatic monomer.
Claim 18
Dependent Claim
20 words
The method of claim 16 wherein the resin has a crosslinked copolymer matrix of styrene/DVB, functionalized with sulfonic acid groups.
Claim 19
Dependent Claim
21 words
An improved stability cation exchange resin having an effective amount of antioxidant incorporated therein prepared by the method of claim 1.
Claim 20
Dependent Claim
21 words
An improved stability cation exchange resin having an effective amount of antioxidant incorporated therein prepared by the method of claim 17.
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) | 1993-11-26 | 1994-05-28 | 1994-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-26 | 1998-05-28 | 1998-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-26 | 2002-05-28 | 2002-11-27 | $7700.00 | Window Closed / Lapsed |