| 主权项 |
1. A method for treating scale, comprising adding an antiscale agent comprising an anionic polymer to an aqueous system in need of scale treatment, in an amount effective to reduce or inhibit scale in the aqueous system; wherein the anionic polymer comprises recurring units of the formula (I) and recurring units of the formula (II): wherein: A1 is —CH2— or a group of the formula (III): A2 is —CH2—, —C(═O)NHC(CH3)2CH2—, or a bond; R1, R2 and R3 are each individually —CH3 or —H; and at least one of M1+, M2+ and M3+ is an organic cation, the organic cations represented by M1+, M2+ and M3+ together being present in an amount that is effective to increase the biodegradability of the anionic polymer greater than 56% relative to a comparable anionic polymer in which M1+, M2+ and M3+ are inorganic cations; wherein at least one of M1+, M2+, and M3+ is selected from the group consisting of +NH3(CH3), +NH2(CH3)2, +NH3(CH2CH2OH), +NH2(CH2CH2OH)2, and mixtures thereo; and wherein the anionic polymer comprises at least one metal cation. |
