| 摘要 |
A method for controlling corrosion in an aqueous system which comprises incorporating in the system at least one phosphonate of the formula: <CHEM> in which R1 represents hydrogen or a C1-C4 alkyl group and R2 represents -COOH or -PO3H2 or a salt thereof, and at least one polyampholyte which possesses recurring units of the formula <CHEM> and either recurring units of the formula: <CHEM> or recurring units of the formula <CHEM> in which R1 represents hydrogen or a C1-C4 alkyl group, X represents hydrogen or -COOH, Y represents <CHEM> in which Z represents -O- or -NH-, n is 2 or 3 and R2, R3, R4 and R5 individually represent C1-C4 alkyl, especially methyl or ethyl, and A represents an anion especially Cl, Br, CH3SO4 or C2H5SO4, or a salt thereof. |
