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PPMA is formed by the P-C bonding,hard to be hydrolyzed, a low-phosphorus scale inhibitor and cathode corrosion inhibitor. Due to including phosphate group (corrosion inhibition and chelation) and carboxylic acid group (dispersion), PPMA has double synergic effects and better performance than HPMA and MA/AA. It has good corrosion inhibition on brass, good dispersion on different scale salt such as CaCO3、Ca3(PO4)2、MgSiO3. PPMA has good compatibility with zinc salt. When used together, the zinc ion is more stable, the solubility of zinc salt can be improved to stay dissolved state even at pH9.5, and the corrosion degree of carbon steel can be decreased to below 0.1mm/a. When built with benzotriazole, it can inhibit copper, aluminum and alloy corrosion.