US3950296A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reversible coacervation of anion-containing aqueous disperse systems with amphoteric polyelectrolytes
Assignee: Dow Chemical Co
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Filing: 1974-10-21
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Granted: 1976-04-13
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Expires: 1994-10-21
Abstract
Abstract Fluid, stable compositions containing aqueous disperse systems of (1) anionizable material, e.g., an aqueous solution of an organic polymer having carboxylate functionality, and (2) a water-dispersible amphoteric polyelectrolyte, e.g., a copolymer of 2-aminoethyl methacrylate and methacrylic acid, reversibly coavervated by maintaining the pH of the composition at a value below the isoelectric point of the amphoteric polyelectrolyte and a value at which the disperse material contains anions. The resulting coacervate is readily redispersed by increasing the pH of the coacervate to a value above the isoelectric point of the polyelectrolyte. Such compositions are useful in warp sizing of yarns and in other coating applications.
Inventors
- 👤 Donald A. Kangas
- 👤 W. Robert Neuendorf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:48
CPC Classifications
D; D06; D06M; D06M15/00; D06M15/19; D06M15/21; D06M15/263; B; B01; B01D; B01D17/00; B01D17/02; B01D17/04; B01D17/047; B01J; B01J13/00; B01J13/0052; B01J13/0065; C; C02; C02F; C02F1/00; C02F1/52; C02F1/54; D06M15/267; Y; Y10; Y10S; Y10S526/00; Y10S526/923
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
172 words
A composition comprising an aqueous disperse system of an anionizable disperse material and an amount of an inherently water-dispersible amphoteric polyelectrolyte effective to reversibly coacervate the system at a value of pH which is at or below the isoelectric point of the polyelectrolyte and at which value the anionizable material contains anions, said disperse material being particles of the dispersed or solvated material of an aqueous dispersion or aqueous solution wherein one or more anionizable groups reside in or on the surface of each of the dispersed or solvated particles, said anionizable group being any group that will form an anion at some value of pH below the isoelectric point of the amphoteric polyelectrolyte, said polyelectrolyte having an isoelectric point at pH of at least 6 and containing ionizable cationic groups having a pKa in the range from about 4 to about 11 and ionizable anionic groups having a pKa less than about 6, said polyelectrolyte having a molar ratio of ionizable cationic groups to ionizable anionic groups of at least 1:1.
Claim 2
Dependent Claim
172 words
A composition comprising an aqueous disperse system of an anionizable disperse material and an amount of an inherently water-dispersible amphoteric polyelectrolyte effective to reversibly coacervate the system at a value of pH which is at or below the isoelectric point of the polyelectrolyte and at which value the anionizable material contains anions, said disperse material being particles of the dispersed or solvated material of an aqueous dispersion or aqueous solution wherein one or more anionizable groups reside in or on the surface of each of the dispersed or solvated particles, said anionizable group being any group that will form an anion at some value of pH below the isoelectric point of the amphoteric polyelectrolyte, said polyelectrolyte having an isoelectric point at pH of at least 6 and containing ionizable cationic groups having a pKa in the range from about 4 to about 11 and ionizable anionic groups having a pKa less than about 6, said polyelectrolyte having a molar ratio of ionizable cationic groups to ionizable anionic groups of at least 1:1.
Claim 3
Dependent Claim
24 words
The composition according to claim 1 wherein the polyelectrolyte has an isoelectric point at pH in the range from about 7 to about 10.
Claim 4
Dependent Claim
33 words
The composition according to claim 2 wherein the polyelectrolyte has a molar ratio of ionizable cationic groups to ionizable anionic groups of at least 1:1 in the range from about 2:1 to 10:1.
Claim 5
Dependent Claim
19 words
The composition according to claim 3 wherein the cationic groups are amino groups and anionic groups are carboxyl groups.
Claim 6
Dependent Claim
26 words
The composition according to claim 4 wherein the polyelectrolyte is a copolymer of an aminoalkyl ester of α,β-ethylenically unsaturated carboxylic acid and α,β-ethylenically unsaturated carboxylic acid.
Claim 7
Dependent Claim
25 words
The composition according to claim 5 wherein the aqueous disperse system comprises an anionically stabilized latex of a normally solid, water-insoluble, plastic organic addition polymer.
Claim 8
Dependent Claim
14 words
The composition according to claim 5 wherein the anionizable material is a water-soluble polymer.
Claim 9
Dependent Claim
14 words
The composition according to claim 7 wherein the anionizable material is an anionic surfactant.
Claim 10
Dependent Claim
19 words
The composition according to claim 8 wherein the anionizable material is an anionically stabilized dispersion of an inorganic solid.
Claim 11
Dependent Claim
29 words
The composition according to claim 1 wherein the amount of polyelectrolyte is sufficient to provide from about 1 to 100 cationic groups per 10 anions in the anionizable material.
Claim 12
Dependent Claim
121 words
A process for coacervating and then redispersing an aqueous disperse system of an anionizable disperse material which comprises (1) combining the disperse system and the amphoteric polyelectrolyte of claim 1 in an amount effective to coacervate the disperse system at a value of pH which is at or below the isoelectric point of the polyelectrolyte and at which value the anionizable material contains anions, (2) maintaining the pH of the combined disperse system and polyelectrolyte at said value thereby coacervating the disperse system and (3) adjusting the pH of the coacervated system to a value above isoelectric point or to a low value of pH at which the anionizable no longer contains a significant number of anions thereby redispersing the coacervate.
Claim 13
Dependent Claim
59 words
A process according to claim 11 for latent coacervation of the aqueous disperse system wherein the disperse system and polyelectrolyte are combined at pH above the isoelectric point of the polyelectrolyte and the pH of the combined disperse system and polyelectrolyte is lowered to a pH below the isoelectric point of the polyelectrolyte without the addition of chemical agent.
Claim 14
Dependent Claim
15 words
The process according to claim 12 wherein the pH is lowered by volatilization of base.
References Cited (Backward Citations)
US2995512A
Cited
US2832746A
Cited
US3024221A
Cited
US3006868A
Cited
US3147301A
Cited
US3215647A
Cited
US3389109A
Cited
US3528928A
Cited
US3644258A
Cited
US3822230A
Cited
US3843585A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-04-13 | 1979-10-13 | 1980-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-13 | 1983-10-13 | 1984-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-13 | 1987-10-13 | 1988-04-13 | $7700.00 | Window Closed / Lapsed |