Patent US3919140A successfully refreshed from Google Patents.
US3919140A
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Process for producing acrylamide polymers in an acetone-water solvent system
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1974-12-27
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Granted: 1975-11-11
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Expires: 1994-12-27
Abstract
Abstract A process for producing acrylamide polymers involves polymerization of acrylamide or methacrylamide or polymerizable monovinylic monomers containing predominantly acrylamide or methacrylamide in a mixture of acetone and water in the presence of polyvinyl alcohol, the amount of acetone being from about 23 to 30 %, preferably up to 29.5 %, by weight based on the weight of the acetone-water mixture and the amount of polyvinyl alcohol being from 0.5 to 4 % by weight based on the weight of the polymerizable monomers. The water-soluble acrylamide polymers obtained by this process are in the form of a powder and possess high intrinsic viscosity or high molecular weight so that they are useful as flocculating agents.
Inventors
- 👤 Hidekazu Hirata
- 👤 Siro Sakai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:35
CPC Classifications
C; C08; C08F; C08F20/00; C08F20/02; C08F20/52; C08F20/54; C08F20/56; C02; C02F; C02F1/00; C02F1/52; C02F1/54
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
77 words
A PROCEZSS FOR PRODUCING ACRYAMIDE POLYMERS WHICH COMPRISES CONDUCTING THE POLYMERIZATION OF ACRYLAMIDE OR METHACRYLAMIDE OR POLYMERIZABLE MONOVINYLIC MONOMERS CONTAINING PREDOMINANTLY ACRYLAMIDE OR METHACRYLAMIDE IN A MIXTURE OF ACETONE AND WATER IN THE PRESENCE OF POLYVINYL ALCOHOL, THE AMOUNT OF ACETONE BEING FROM 23 TO 29.5% BY WEIGHT BASED ON THE WEIGHT OF THE ACETONE-WATER MIXTURE AND THE AMOUNT OF POLYVINYL ALCOHOL BEING FROM 0.5 TO 4% BY WEIGHT BASED ON THE WEIGHT OF THE POLYMERIZABLE MONOMERS.
Claim 2
Dependent Claim
77 words
A PROCEZSS FOR PRODUCING ACRYAMIDE POLYMERS WHICH COMPRISES CONDUCTING THE POLYMERIZATION OF ACRYLAMIDE OR METHACRYLAMIDE OR POLYMERIZABLE MONOVINYLIC MONOMERS CONTAINING PREDOMINANTLY ACRYLAMIDE OR METHACRYLAMIDE IN A MIXTURE OF ACETONE AND WATER IN THE PRESENCE OF POLYVINYL ALCOHOL, THE AMOUNT OF ACETONE BEING FROM 23 TO 29.5% BY WEIGHT BASED ON THE WEIGHT OF THE ACETONE-WATER MIXTURE AND THE AMOUNT OF POLYVINYL ALCOHOL BEING FROM 0.5 TO 4% BY WEIGHT BASED ON THE WEIGHT OF THE POLYMERIZABLE MONOMERS.
Claim 3
Dependent Claim
30 words
The process according to claim 1, wherein the concentration of the polymerizable monomers is from 10 to 30% by weight based on the total weight of the polymerization reaction mixture.
Claim 4
Dependent Claim
20 words
The pRocess according to claim 2, wherein the concentration of the polymerizable monomers is from 15 to 25% by weight.
Claim 5
Dependent Claim
27 words
The process according to claim 1, wherein the amount of polyvinyl alcohol is from 1 to 2% by weight based on the weight of the polymerizable monomers.
Claim 6
Dependent Claim
43 words
The process according to claim 1, wherein the polymerizable monovinylic monomers other than acrylamide and methacrylamide is a member or a combination of members selected from the group consisting of acrylonitrile, an anionic monomer and a basic monomer which become cationic when quaternized.
Claim 7
Dependent Claim
26 words
The process according to claim 5, wherein the anionic monomer is acrylic acid, methacrylic acid or their metal or ammonium salt, sodium vinylsulfonate or sulfonated styrene.
Claim 8
Dependent Claim
15 words
The process according to claim 5, wherein the basic monomer is vinylpyridine or dialkylaminoalkyl methacrylate.
Claim 9
Dependent Claim
21 words
The process according to claim 1, wherein a catalyst which is soluble in a mixture of acetone and water is used.
Claim 10
Dependent Claim
17 words
The process according to claim 8, wherein the catalyst is a radical catalyst or a redox catalyst.
Claim 11
Dependent Claim
16 words
The process according to claim 9, wherein the radical catalyst is a water-soluble peroxide and azobisisobutyronitrile.
Claim 12
Dependent Claim
18 words
The process according to claim 10, wherein the water-soluble peroxide is hydrogen peroxide, potassium persulfate or ammonium persulfate.
Claim 13
Dependent Claim
23 words
The process according to claim 9, wherein the redox catalyst is potassium persulfate and sodium hydrogen sulfite, an amine or sodium formaldehyde sulfoxylate.
Claim 14
Dependent Claim
31 words
The process according to claim 8, wherein the catalyst is used in an amount of from 0.01 to 0.2% by weight based on the weight of the monomeric component or components.
Claim 15
Dependent Claim
16 words
The process according to claim 1, wherein a dispersion stabilizer is present in the reaction system.
Claim 16
Dependent Claim
24 words
The process according to claim 14, wherein the dispersion stabilizer is a water-soluble high molecular weight compound, an inorganic salt or a buffering agent.
Claim 17
Dependent Claim
16 words
The process according to claim 15, wherein the water-soluble high molecular weight compound is carboxymethyl cellulose.
Claim 18
Dependent Claim
22 words
The process according to claim 15, wherein the inorganic salt is potassium chloride, sodium chloride, ammonium chloride, sodium sulfate or sodium carbonate.
Claim 19
Dependent Claim
18 words
The process according to claim 15, wherein the buffering agent is sodium acetate-acetic acid or ammonium chloride-ammonia water.
Claim 20
Dependent Claim
16 words
The process according to claim 1, wherein the reaction temperature is from 20* to 30* C.
References Cited (Backward Citations)
US3301809A
Cited
US3509113A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-10 | 1979-05-12 | 1979-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-10 | 1983-05-12 | 1983-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-10 | 1987-05-12 | 1987-11-11 | $7700.00 | Window Closed / Lapsed |