Corrosion inhibition with amine adducts of maleic anhydride polymers

Claim 1

A composition useful for inhibiting the corrosion of metallic surfaces of aqueous systems, comprising zinc and a polymer, wherein the polymer and zinc components are present in a ratio of from about 1 to 5 to about 50 to 1, respectively, said polymer being selected from the group consisting of: a. polymers having recurring units of the formula: ##STR9## wherein M + may be H + , alkali metal cation, or quaternary ammonium cation of the formula: ##STR10## wherein for all of the above formulas, R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 are each independently selected from the group consisting of hydrogen, alkyl of from one to ten carbon atoms, and substituted alkyl of from one to ten carbon atoms, where the substituent is hydroxyl, carboxyl, and alkali metal and ammonium carboxylate; and wherein n is an integer of from 2 to 100 such that the polymer has a weight average molecular weight of from about 200 to about 10,000; and wherein for the polymer component of the composition, the molecular ratio of amine to maleic anhydride is from about 0.1 to about 2.0; and b. polymers having recurring units of the formula: ##STR11## wherein R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 have the same meaning as above; wherein p is an integer of from 1 to 6; wherein m is an integer of from 2 to 100; and wherein n is an integer of from 2 to about 100 such that the polymer has a weight average molecular weight of from about 200 to about 10,000, provided that, for n not equal to m, the lesser of m or n is multiplied by a factor such that n=m; and wherein for the polymer component of the composition, the molecular ratio of amine to maleic anhydride is from about 0.1 to about 2.0.

Claim 11

A method of inhibiting the corrosion of metallic surfaces of an aqueous system comprising maintaining in the aqueous content of the said system a concentration level between 0.1 and 1,000 parts per million by weight of the total said aqueous content, of a composition comprising zinc and a polymer, wherein the polymer and zinc components are present in a ratio of from about 1 to 5 to about 50 to 1, respectively, said polymer being selected from the group consisting of: a. polymers having recurring units of the formula: ##STR17## wherein M + may be H + , alkali metal cation, or quaternary ammonium cation of the formula: ##STR18## wherein for all of the above formulas, R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 are each independently selected from the group consisting of hydrogen, alkyl of from one to ten carbon atoms, and substituted alkyl of from one to ten carbon atoms, where the substituent is hydroxyl; carbonyl; and carboxylic acid groups, and alkali metal ion and ammonium salts thereof; and wherein n is an integer of from 2 to 100 such that the polymer has a weight average molecular weight of from about 200 to about 10,000; and wherein for the polymer component of the composition, the molecular ratio of amine to maleic anhydride is from about 0.1 to about 2.0; and b. polymers having recurring units of the formula: ##STR19## wherein R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 have the same meaning as above; wherein p is an integer of from 1 to 6; wherein m is an integer of from 2 to about 100; and wherein n is an integer of from 2 to about 100 such that the polymer has a weight average molecular weight of from about 200 to about 10,000, provided that, for n not equal to m, the lesser of m or n is multiplied by a factor such that n=m; and wherein for the polymer component of the composition, the molecular ratio of amine to maleic anhydride is from about 0.1 to about 2.0.

Claim 12

A method of inhibiting the corrosion of metallic surfaces of an aqueous system comprising maintaining in the aqueous content of the said system a concentration level between 0.1 and 1,000 parts per million by weight of the total said aqueous content, of a composition comprising zinc and a polymer, wherein the polymer and zinc components are present in a ratio of from about 1 to 5 to about 50 to 1, respectively, said polymer being selected from the group consisting of: a. polymers having recurring units of the formula: ##STR17## wherein M + may be H + , alkali metal cation, or quaternary ammonium cation of the formula: ##STR18## wherein for all of the above formulas, R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 are each independently selected from the group consisting of hydrogen, alkyl of from one to ten carbon atoms, and substituted alkyl of from one to ten carbon atoms, where the substituent is hydroxyl; carbonyl; and carboxylic acid groups, and alkali metal ion and ammonium salts thereof; and wherein n is an integer of from 2 to 100 such that the polymer has a weight average molecular weight of from about 200 to about 10,000; and wherein for the polymer component of the composition, the molecular ratio of amine to maleic anhydride is from about 0.1 to about 2.0; and b. polymers having recurring units of the formula: ##STR19## wherein R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 have the same meaning as above; wherein p is an integer of from 1 to 6; wherein m is an integer of from 2 to about 100; and wherein n is an integer of from 2 to about 100 such that the polymer has a weight average molecular weight of from about 200 to about 10,000, provided that, for n not equal to m, the lesser of m or n is multiplied by a factor such that n=m; and wherein for the polymer component of the composition, the molecular ratio of amine to maleic anhydride is from about 0.1 to about 2.0.