US4464508A
Expired / Lapsed
US
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Water-in-oil emulsions of water-soluble cationic polymers having improved stability
Assignee: Dow Chemical Co
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Filing: 1982-09-30
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Granted: 1984-08-07
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Expires: 2002-09-30
Abstract
Abstract Water-in-oil emulsions of water-soluble cationic polymers, e.g., a copolymer of acrylamide and acryloylethyl trimethyl ammonium chloride, exhibiting improved emulsion stability are prepared by incorporating a water-soluble salt of a monovalent anion, e.g., ammonium chloride, into the aqueous phase at some point prior to polymerization.
Inventors
- 👤 James P. Easterly, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:35
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/10; C08K3/14; C08F; C08F2/00; C08F2/32
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
67 words
A water-in-oil emulsion comprising (1) a discontinuous aqueous phase containing a water-soluble cationic polymer which aqueous phase is dispersed as colloidal size particles or droplets in (2) a continuous oil phase wherein the emulsion contains an emulsion stabilizing amount of a water-soluble salt of a monovalent anion and an emulsifying amount of a water-in-oil emulsifier, said salt added prior to polymerization to form the water-soluble cationic polymer.
Claim 2
Dependent Claim
67 words
A water-in-oil emulsion comprising (1) a discontinuous aqueous phase containing a water-soluble cationic polymer which aqueous phase is dispersed as colloidal size particles or droplets in (2) a continuous oil phase wherein the emulsion contains an emulsion stabilizing amount of a water-soluble salt of a monovalent anion and an emulsifying amount of a water-in-oil emulsifier, said salt added prior to polymerization to form the water-soluble cationic polymer.
Claim 3
Dependent Claim
19 words
The emulsion of claim 1 wherein the salt is an alkali metal or ammonium salt of a monovalent cation.
Claim 4
Dependent Claim
12 words
The emulsion of claim 2 wherein the anion is halide or nitrate.
Claim 5
Dependent Claim
16 words
The emulsion of claim 3 wherein the salt is ammonium chloride, sodium nitrate or sodium chloride.
Claim 6
Dependent Claim
30 words
The emulsion of claim 1 wherein the amount of salt is from about 2 to about 30 weight percent based on total monomer(s) used to form the water-soluble cationic polymer.
Claim 7
Dependent Claim
24 words
The emulsion of claim 1 wherein the cationic polymer is a polymer of a quaternary ammonium alkyl ester of an ethylenically unsaturated carboxylic acid.
Claim 8
Dependent Claim
33 words
The emulsion of claim 6 wherein the cationic polymer is a copolymer of acrylamide with from about 5 to about 15 mole percent of methacryloylethyl trimethyl ammonium chloride or acryloylethyl trimethyl ammonium chloride.
Claim 9
Dependent Claim
76 words
A method for preparing the emulsion of claim 1, 5 or 7 which comprises (1) forming a stable water-in-oil emulsion (monomeric precursor) containing at least one water-soluble cationic monomer in the aqueous phase which is dispersed in a continuous oil phase, said emulsion containing a stabilizing amount of a water-soluble salt of a monovalent anion and an emulsifying amount of a water-in-oil emulsifier; and (2) subjecting the monomeric precursor to conditions sufficient to polymerize the monomer.
Claim 10
Dependent Claim
17 words
A method of claim 8 wherein said cationic monomer is N-(trimethylammoniumpropyl)-methacrylamide chloride or diallyl dimethyl ammonium chloride.
References Cited (Backward Citations)
US4242247A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-08-07 | 1988-02-06 | 1988-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-07 | 1992-02-06 | 1992-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-07 | 1996-02-06 | 1996-08-07 | $7700.00 | Window Closed / Lapsed |