US4297256A
Expired / Lapsed
US
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Preparation of water-immiscible, acid-soluble N-(aminomethyl)-α,.beta.
Assignee: Dow Chemical Co
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Filing: 1979-12-26
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Granted: 1981-10-27
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Expires: 1999-12-26
Abstract
Abstract Water-immiscible, acid-soluble N-(aminomethyl)-α,β-ethylenically unsaturated carboxamides such as N-(diethylaminomethyl)acrylamide are readily prepared by (1) reacting under acidic conditions a carboxamide such as acrylamide with a lower aldehyde such as formaldehyde and a moderately water-soluble secondary amine such as diethylamine and (2) recovering the resulting water-immiscible aminomethyl derivative of carboxamide from the acidic reaction mixture by adjusting the pH of the reaction mixture to a value of 7 or higher, whereby the water-immiscible derivative separates from the reaction mixture.
Inventors
- 👤 Charles J. McDonald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:10
CPC Classifications
C; C08; C08F; C08F20/00; C08F20/02; C08F20/52; C08F20/54; C08F20/60
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
134 words
A process for preparing an acid soluble water-immiscible N-(aminomethyl)carboxamide (cationic carboxamide) which comprises (1) contacting a reaction mixture comprising an aqueous phase and a carboxamide reactant represented by the formula: ##STR5## wherein R 1 is hydrogen or alkyl and R 2 is hydrogen or an inert substituent with an aldehyde having 1 to 3 carbons and a moderately water-soluble amine under conditions including a pH of less than about 7 sufficient to cause reaction of the carboxamide reactant, aldehyde and amine to form at least 5 mole percent of the water-immiscible cationic carboxamide based on moles of the carboxamide reactant and (2) thereafter increasing the pH of the resulting reaction mixture to a value of at least 7, thereby causing the water-immiscible cationic carboxamide to separate from the aqueous phase of the reaction mixture.
Claim 2
Dependent Claim
134 words
A process for preparing an acid soluble water-immiscible N-(aminomethyl)carboxamide (cationic carboxamide) which comprises (1) contacting a reaction mixture comprising an aqueous phase and a carboxamide reactant represented by the formula: ##STR5## wherein R 1 is hydrogen or alkyl and R 2 is hydrogen or an inert substituent with an aldehyde having 1 to 3 carbons and a moderately water-soluble amine under conditions including a pH of less than about 7 sufficient to cause reaction of the carboxamide reactant, aldehyde and amine to form at least 5 mole percent of the water-immiscible cationic carboxamide based on moles of the carboxamide reactant and (2) thereafter increasing the pH of the resulting reaction mixture to a value of at least 7, thereby causing the water-immiscible cationic carboxamide to separate from the aqueous phase of the reaction mixture.
Claim 3
Dependent Claim
70 words
The process of claim 1 wherein the amine is a secondary amine represented by the formula: HN(R.sub.3).sub.2 wherein each R 3 is individually hydrocarbyl or inertly substituted hydrocarbyl wherein hydrocarbyl has 2 or more carbons and the cationic carboxamide is represented by the formula: ##STR6## wherein R 1 , R 2 and R 3 are as defined herein and R 4 is hydrogen or alkyl having one or two carbons.
Claim 4
Dependent Claim
31 words
The process of claim 2 wherein the ingredients of the reaction mixture are combined in an aqueous medium such that the pH of the reaction mixture is less than about 5.
Claim 5
Dependent Claim
28 words
The process of claim 2 wherein R 1 is hydrogen, methyl or ethyl, R 2 is hydrogen or alkyl and R 3 is alkyl, alkenyl, hydroxyalkyl or aminoalkyl.
Claim 6
Dependent Claim
43 words
The process of claim 4 wherein the carboxamide reactant is acrylamide, the aldehyde is formaldehyde or a material selected from paraformaldehyde, formalin and trioxymethane, the amine is a diethylamine, dibutylamine or diallylamine, and the pH of the reaction mixture is 3 or less.
Claim 7
Dependent Claim
35 words
The process of claim 1 wherein the reaction mixture is dissolved in an aqueous medium and dispersed in an oil phase to form a water-in-oil emulsion prior to the reaction to form the cationic carboxamide.
Claim 8
Dependent Claim
30 words
The process of claim 1 wherein the amine and aldehyde are prereacted to form an adduct which is immiscible with an aqueous phase having a pH of 7 or more.
Claim 9
Dependent Claim
29 words
The process of claim 2 which process comprises the additional step of subjecting the cationic carboxamide to conditions of free-radical initiated addition polymerization at pH less than about 7.
Claim 10
Dependent Claim
35 words
The process of claim 8 wherein the cationic carboxamide dissolved in the aqueous phase of a water-in-oil emulsion is subjected to polymerization conditions thereby forming a water-in-oil emulsion wherein the aqueous phase contains the polymer.
Claim 11
Dependent Claim
30 words
The process of claim 2 wherein the cationic carboxamide is quaternized by contacting the cationic carboxamide with a quaternizing agent to form a reaction mixture having a pH below 7.
Claim 12
Dependent Claim
58 words
The process of claim 10 wherein the cationic carboxamide is an N-(dihydrocarbylaminomethyl)acrylamide wherein hydrocarbyl is ethyl, butyl or allyl and the quaternizing agent is an alkyl halide or dialkyl sulfate wherein alkyl is 1 or 2 carbons and alkylene is 2 to 3 carbons and the pH of the reaction mixture is from about 3 to about 5.
Claim 13
Dependent Claim
59 words
The process of claim 1 wherein the cationic carboxamide monomer or mixture thereof with one or more other water-immiscible monomers residing in the oil phase of an oil-in-water emulsion is subjected to emulsion polymerization conditions to form an aqueous dispersion wherein the polymer of the cationic carboxamide exists as a colloidal size particulate dispersed in a continuous aqueous phase.
Claim 14
Dependent Claim
10 words
The process of claim 2 wherein R 3 is hydrocarbyl.
Claim 15
Dependent Claim
11 words
The process of claim 13 wherein hydrocarbyl is alkyl or alkenyl.
Claim 16
Dependent Claim
10 words
The process of claim 14 wherein R 3 is alkyl.
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) | 1984-10-26 | 1985-04-27 | 1985-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-26 | 1989-04-27 | 1989-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-26 | 1993-04-27 | 1993-10-27 | $7700.00 | Window Closed / Lapsed |