AA/AMPS is the copolymer of acrylic acid and 2-acrylanmido-2-methylpropanesulfonic acid (AMPS). Due to including carboxylic group (scale inhibition and dispersion) and sulfonic acid group (strong polarity) in this copolymer, AA/AMPS has high calcium tolerance and good scale inhibition for calcium phosphate, calcium carbonate and zinc scale. When built with organophosphines, the synergic effect is obvious. AA/AMPS is suitable to be used in water quality of high pH and high alkaline, it is one of the ideal scale inhibitor and dispersant on high concentration index.