Patent EP0225596A2 successfully refreshed from Google Patents.
EP0225596A2
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Method of producing sulfomethyl polyacrylamide polymers and sulfomethylamide unit containing polymers
Assignee: ChampionX LLC
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Filing: 1986-12-03
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Granted: —
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Expires: 2006-12-03
Abstract
Abstract Polyacrylamide is reacted with formaldehyde and bisulfite at a temperature of at least about 100 DEG C and preferably at an initial reaction mixture pH of less than about 12, preferably about 3 to about 8, to produce sulfomethylpolyacrylamide. Sulfomethylpolyacrylamide polymers are provided which have outstanding properties such as water treatment agents, drilling field dispersants and flocculents.
Inventors
- 👤 Dodd W. Fong
- 👤 David J. Kowalski
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 00:22
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/34; C08F2800/00; C08F2800/10
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
34 words
A method of producing sulfomethyl polyacrylamide polymers characterized in that an acrylamide units containing polymer is reacted with formaldehyde and bisulfite by heating together and agitating at a temperature of at least about 100°C.
Claim 2
Independent Claim
34 words
A method of producing sulfomethyl polyacrylamide polymers characterized in that an acrylamide units containing polymer is reacted with formaldehyde and bisulfite by heating together and agitating at a temperature of at least about 100°C.
Claim 3
Dependent Claim
20 words
The method of claim 1 characterized in that the initial pH of the reaction mixture is less than about 12.
Claim 4
Dependent Claim
23 words
The method of claim 2, characterized in that the initial pH of the reaction mixture is adjusted between about 3 and about 8.
Claim 5
Independent Claim
23 words
The method of any of claims 1 to 3, characterized in that the reaction temperature is maintained from about 110°C to about 250°C.
Claim 6
Independent Claim
33 words
The method according to any of claims 1 to 4 characterized in that the starting polymer is an acrylamide-acrylic acid copolymer, preferably with a ratio of about 75 mol percent of acrylamide units.
Claim 7
Independent Claim
28 words
The method according to any of claims 1 to 5, characterized in that the reaction is performed within a period of about 15 minutes to about 8 hours.
Claim 8
Independent Claim
18 words
The method according to any of claims 1 to 6 characterized in that the reaction medium is aqueous.
Claim 9
Dependent Claim
9 words
Sulfomethylated polymer characterized in that it comprises poly(sulfomethylacrylamide) units.
Claim 10
Dependent Claim
9 words
Sulfomethylated polymer characterized in that it comprises poly(sulfomethylacrylamide) units.
Claim 11
Dependent Claim
25 words
Sulfomethylated polymer according to claim 8 characterized by at least three functional groups selected from the group consisting of carboxylate, primary amide and sulfomethylamide groups.
Claim 12
Dependent Claim
14 words
Sulfomethylated polymer, producible according to the method of any of claims 1 to 7.
Claim 13
Dependent Claim
1 words
Sulfomethylpolyacrylamide.
Claim 14
Dependent Claim
1 words
Sulfomethylpolyacrylamide.
Claim 15
Dependent Claim
40 words
Sulfomethylated polymer according to any of claims 8 to 10, characterized in that it comprises about 10 to 20% of sulfomethylamide and about 30 to 40% of carboxylate groups, the percent being related to the mol proportion in the polymer.
Claim 16
Dependent Claim
38 words
Sulfomethylated polymer according to any of the preceding claims, characterized in that its carbon-13 NMR spectrum reveals signals at 56,6 (methylene) and 178 (secondary amide carbonyl) and IR absorption bands at 1.200, 1.050 and 1.500 cm -1 .
Claim 17
Dependent Claim
34 words
Sulfomethylated polymer according to any of claims 8 to 10, 12 and 13, characterized in that it is a copolymer or a terpolymer of acrylamide and/or its homologs with acrylic acid and/or its homologs.
References Cited (Backward Citations)
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