Preparation of a manniched polyacrylamide quarternaries thereof

Claim 2

An improved method for the preparation of a cationically modified acrylamide polymer, said cationically modified polymers generally being prepared by admixing together: a. an acrylamide polymer; b. a lower aliphatic aldehyde containing 1-3 carbon atoms; and c. a lower alkyl secondary amine containing 2-6 carbon atoms; in a mole ration of amide groups on said acrylamide polymer to b and c above of from 1.0:0.5:0.5 to 1.0:1.5:1.5, the improvement comprising: A. preparing a 5-40% by weight aqueous solution of a water soluble acrylamide polymer; B. adjusting the pH of said aqueous solution of a water soluble acrylamide polymer to between 4.5-5.5; C. adding to the aqueous solution of the acrylamide polymer with mixing, an aqueous solution of a water soluble lower aliphatic aldehyde containing 1-3 carbon atoms in a mole ratio of aldehyde to amide functionality present on said acrylamide polymer of 0.5:1 to 1.1:1 whereby an aqueous acrylamide-aldehyde solution is prepared; D. adding to said aqueous acrylamide-formaldehyde solution with mixing a lower aliphatic secondary amine containing 2-6 carbon atoms in a mole ratio of the lower aliphatic aldehyde added to said acrylamide polymer in step C to amine of 1.0:1.0 to 1.0:1.2, whereby the secondary amine is reacted with the acrylamide-aldehyde solution and a stable cationically modified acrylamide polymer is formed; and then, E. recovering an aqueous solution of cationically modified acrylamide polymer.

Claim 3

The improvement of claim 1 wherein the pH of said aqueous solution of a water soluble acrylamide polymer is 5.0-5.2.

Claim 4

The improvement of claim 1 wherein the secondary amine is dimethyl amine.

Claim 5

The improvement of claim 1 wherein the aldehyde is formaldehyde.

Claim 6

The improvement of claim 1 wherein the aqueous solution of the acrylamide polymer is maintained at a temperature of from 35° C. to 65° C. during the addition of the aldehyde.

Claim 7

An improved method for the preparation of a cationically modified quaternized acrylamide polymer, said cationically modified quaternized polymers generally being prepared by admixing together. a. an acrylamide polymer; b. a lower aliphatic aldehyde containing 1-3 carbon atoms; and c. a lower alkyl secondary amine containing 2-6 carbon atoms; in a mole ratio of amide groups on said acrylamide polymer to b and c above of from 1.0:0.5:0.5 to 1.0:1.5:1.5, and then quaternizing the resultant cationically modified acrylamide polymer, the improvement comprising: A. preparing a 5-40% by weight aqueous solution of a water soluble acrylamide polymer; B. adjusting the pH of said aqueous solution of a water soluble acrylamide polymer to between 4.5-5.5; C. adding to the aqueous solution of a acrylamide polymer with mixing, an aqueous solution of a water soluble lower aliphatic aldehyde containing 1-3 carbon atoms in a mole ratio of aldehyde to amide functionality present on said acrylamide polymer of 0.5:1 to 1.1:1 whereby an aqueous acrylamide-formaldehyde solution is prepared; D. adding to said aqueous acrylamide-formaldehyde solution with mixing a lower aliphatic secondary amine containing 2-6 carbon atoms in a mole ratio of the lower aliphatic aldehyde added to said acrylamide polymer in step C to amine of 1.0:1.0 to 1.0:1.2, whereby the secondary amine is reacted with the acrylamide-formaldehyde solution and a cationically modified acrylamide polymer is formed; E. adding to said dilute solution of a cationically modified acrylamide polymer with mixing a sufficient quantity of a mineral acid so as to adjust the pH of said dilute solution of a cationically modified acylamide polymer to 7.5-8.5; F. adding to said dilute solution of a cationically modified acrylamide polymer with mixing and at a temperature of from 80°-120° F. a quaternizing agent from the group consisting of lower alkyl halides containing 1-4 carbon atoms, in a mole ratio of quaternizing agent to secondary amine added in step 1 above of from 1.0:1.0 to 1.25:1.0; G. maintaining a temperature of from 80°-120° F. for a period of time necessary in order to carry out said quaternization; and then, H. recovering a dilute solution of a water soluble quaternized cationically modified acrylamide polymer.

Claim 8

An improved method for the preparation of a cationically modified quaternized acrylamide polymer, said cationically modified quaternized polymers generally being prepared by admixing together. a. an acrylamide polymer; b. a lower aliphatic aldehyde containing 1-3 carbon atoms; and c. a lower alkyl secondary amine containing 2-6 carbon atoms; in a mole ratio of amide groups on said acrylamide polymer to b and c above of from 1.0:0.5:0.5 to 1.0:1.5:1.5, and then quaternizing the resultant cationically modified acrylamide polymer, the improvement comprising: A. preparing a 5-40% by weight aqueous solution of a water soluble acrylamide polymer; B. adjusting the pH of said aqueous solution of a water soluble acrylamide polymer to between 4.5-5.5; C. adding to the aqueous solution of a acrylamide polymer with mixing, an aqueous solution of a water soluble lower aliphatic aldehyde containing 1-3 carbon atoms in a mole ratio of aldehyde to amide functionality present on said acrylamide polymer of 0.5:1 to 1.1:1 whereby an aqueous acrylamide-formaldehyde solution is prepared; D. adding to said aqueous acrylamide-formaldehyde solution with mixing a lower aliphatic secondary amine containing 2-6 carbon atoms in a mole ratio of the lower aliphatic aldehyde added to said acrylamide polymer in step C to amine of 1.0:1.0 to 1.0:1.2, whereby the secondary amine is reacted with the acrylamide-formaldehyde solution and a cationically modified acrylamide polymer is formed; E. adding to said dilute solution of a cationically modified acrylamide polymer with mixing a sufficient quantity of a mineral acid so as to adjust the pH of said dilute solution of a cationically modified acylamide polymer to 7.5-8.5; F. adding to said dilute solution of a cationically modified acrylamide polymer with mixing and at a temperature of from 80°-120° F. a quaternizing agent from the group consisting of lower alkyl halides containing 1-4 carbon atoms, in a mole ratio of quaternizing agent to secondary amine added in step 1 above of from 1.0:1.0 to 1.25:1.0; G. maintaining a temperature of from 80°-120° F. for a period of time necessary in order to carry out said quaternization; and then, H. recovering a dilute solution of a water soluble quaternized cationically modified acrylamide polymer.

Claim 9

The improvement of claim 6 wherein the pH of said aqueous solution of a water soluble acrylamide polymer in Step B is 5.0-5.2.

Claim 10

The improvement of claim 6 wherein the secondary amine is dimethyl amine.

Claim 11

The improvement of claim 6 wherein the lower aliphatic aldehyde is formaldehyde.

Claim 12

The improvement of claim 6 wherein the aqueous solution of the acrylamide polymer is maintained at a temperature of from 35° C. to 65° C. during the addition of the lower aliphatic aldehyde.

Claim 13

The improvement of claim 6 wherein the lower alkylhalide is methyl chloride.

Claim 14

The improvement of claim 6 wherein the pH of said dilute solution of a cationically modified acrylamide polymer is adjusted to a pH of 8.0-8.5 in Step E.