Patent US4024328A successfully refreshed from Google Patents.
US4024328A
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Method for alkylating aminomethylacrylamide polymers
Assignee: Dow Chemical Co
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Filing: 1975-10-01
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Granted: 1977-05-17
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Expires: 1995-10-01
Abstract
Abstract In the preparation of polyquaternary ammonium salts by alkylation of a dialkylaminomethylacrylamide polymer with an alkyl halide in an aqueous solution of the polymer, more rapid and complete alkylation is obtained when the reaction is carried out in an acidic medium containing a lower alkanol such as methanol.
Inventors
- 👤 Maurice L. Zweigle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:00
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/44
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
73 words
In a method for the preparation of a water-soluble polyquaternary-ammonium derivative of an acrylamide polymer wherein an alkylating agent is reacted with an N-dialkylaminomethyl derivative of said acrylamide polymer in an aqueous medium, the improvement which consists of adjusting the aqueous medium to a pH of 6.5 or less and incorporating therein a catalytic amount of an alkanol containing 1 to 4 carbon atoms prior to contacting said medium with the alkylating agent.
Claim 2
Dependent Claim
73 words
In a method for the preparation of a water-soluble polyquaternary-ammonium derivative of an acrylamide polymer wherein an alkylating agent is reacted with an N-dialkylaminomethyl derivative of said acrylamide polymer in an aqueous medium, the improvement which consists of adjusting the aqueous medium to a pH of 6.5 or less and incorporating therein a catalytic amount of an alkanol containing 1 to 4 carbon atoms prior to contacting said medium with the alkylating agent.
Claim 3
Dependent Claim
31 words
The method of claim 1 wherein the N-dialkylaminomethyl derivative of the acrylamide polymer is a polyacrylamide on which from 20 to 100 percent of the carboxamide groups carry a dimethylaminomethyl substituent.
Claim 4
Dependent Claim
34 words
The method of claim 1 wherein the alkanol is employed in the amount of from about 5 to about 15 percent by weight based on the amount of N-dialkylaminomethyl-acrylamide polymer in the reaction mixture.
Claim 5
Dependent Claim
26 words
The method of claim 3 wherein the reaction is carried out at a temperature of from about 40° C to the boiling temperature of the medium.
Claim 6
Dependent Claim
20 words
The method of claim 1 wherein the alkylating agent is a primary alkyl chloride containing 1 to 4 carbon atoms.
Claim 7
Dependent Claim
24 words
The method of claim 1 wherein the alkylating agent is methyl chloride or ethyl chloride and the reaction is carried out at superatmospheric pressure.
Claim 8
Dependent Claim
12 words
The method of claim 2 wherein the alkylating agent is methyl chloride.
Claim 9
Dependent Claim
34 words
The method of claim 7 wherein the alkanol is employed in the amount of from about 5 to about 15 percent by weight based on the weight of N-dimethylaminomethyl-acrylamide polymer in the reaction mixture.
Claim 10
Dependent Claim
10 words
The method of claim 8 wherein the alkanol is methanol.
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) | 1980-05-16 | 1980-11-15 | 1981-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-16 | 1984-11-15 | 1985-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-16 | 1988-11-15 | 1989-05-17 | $7700.00 | Window Closed / Lapsed |