MA/AA is a low molecular weight polyelectrolyte, a copolymer of maleic anhydride and acrylic acid. It has good dispersant performance against carbonate and scale inhibition for water scale like phosphate. It has good thermal stability, and can be used under high temperature (300℃). MA/AA has good compatibility when used together with other agents. Due to its good scale inhibition and high temperature tolerance properties，MA/AA is widely used in low-pressure boiler, centralized heating, centralized air-conditioner and circulating cool water system. It can also be used as chelating dispersants in woven and dyeing fields.