Method of inhibiting scale with copolymer

Claim 1

A method for inhibiting the deposition of scale due particularly to calcium phosphate and magnesium phosphate formed in a system for treating process water, comprising, adding to said process water from 2 parts per million (ppm) to about 200 ppm of a water-soluble essentially non-crosslinked random copolymer consisting essentially of a copolymer of acrylic acid or methacrylic acid, acrylamide or methacrylamide, and an alkoxyalkyl primary alcohol ester of (meth)acrylic acid, the copolymer having the structural formula ##STR2## wherein, X represents H, or NH 4 , or an alkali metal selected from the group consisting of sodium and potassium; R 1 represents H, or methyl; R 2 represents lower alkyl having from 2 to about 4 carbon atoms; R 3 represents lower alkyl having from 1 to about 10 carbon atoms; n is an integer in the range from 2 to about 6; m is an integer in the range from about 3 to about 70; and, for each y (that is, y=1) x is an integer in the range from about 1 to about 8, and z is a number in the range from 1 to about 0.075; and x, y and z are present in relative heterogeneous order.

Claim 2

A method for inhibiting the deposition of scale due particularly to calcium phosphate and magnesium phosphate formed in a system for treating process water, comprising, adding to said process water from 2 parts per million (ppm) to about 200 ppm of a water-soluble essentially non-crosslinked random copolymer consisting essentially of a copolymer of acrylic acid or methacrylic acid, acrylamide or methacrylamide, and an alkoxyalkyl primary alcohol ester of (meth)acrylic acid, the copolymer having the structural formula ##STR2## wherein, X represents H, or NH 4 , or an alkali metal selected from the group consisting of sodium and potassium; R 1 represents H, or methyl; R 2 represents lower alkyl having from 2 to about 4 carbon atoms; R 3 represents lower alkyl having from 1 to about 10 carbon atoms; n is an integer in the range from 2 to about 6; m is an integer in the range from about 3 to about 70; and, for each y (that is, y=1) x is an integer in the range from about 1 to about 8, and z is a number in the range from 1 to about 0.075; and x, y and z are present in relative heterogeneous order.

Claim 7

A method for inhibiting the deposition of scale due particularly to calcium phosphate formed in a system for pasteurizing milk, comprising, adding to said milk from 0.05 part per million (ppm) to about 10 ppm of a water-soluble essentially non-crosslinked random copolymer consisting essentially of a copolymer of acrylic acid or methacrylic acid, acrylamide or methacrylamide, and an alkoxyalkyl primary alcohol ester of (meth)acrylic acid, the copolymer having the structural formula ##STR3## wherein, X represents H, or NH 4 , or an alkali metal selected from the group consisting of sodium and potassium; R 1 represents H, or methyl; R 2 represents lower alkyl having from 2 to about 4 carbon atoms; R 3 represents lower alkyl having from 1 to about 10 carbon atoms; n is an integer in the range from 2 to about 6; m is an integer in the range from about 3 to about 70; and, for each y (that is, y=1) x is an integer in the range from about 1 to about 8, and z is a number in the range from 1 to about 0.075; and x, y and z are present in relative heterogeneous order.

Claim 8

A method for inhibiting the deposition of scale due particularly to calcium phosphate formed in a system for pasteurizing milk, comprising, adding to said milk from 0.05 part per million (ppm) to about 10 ppm of a water-soluble essentially non-crosslinked random copolymer consisting essentially of a copolymer of acrylic acid or methacrylic acid, acrylamide or methacrylamide, and an alkoxyalkyl primary alcohol ester of (meth)acrylic acid, the copolymer having the structural formula ##STR3## wherein, X represents H, or NH 4 , or an alkali metal selected from the group consisting of sodium and potassium; R 1 represents H, or methyl; R 2 represents lower alkyl having from 2 to about 4 carbon atoms; R 3 represents lower alkyl having from 1 to about 10 carbon atoms; n is an integer in the range from 2 to about 6; m is an integer in the range from about 3 to about 70; and, for each y (that is, y=1) x is an integer in the range from about 1 to about 8, and z is a number in the range from 1 to about 0.075; and x, y and z are present in relative heterogeneous order.