HPMA (Hydrolyzed Polymaleic Anhydride) Supplier South Africa

What Is HPMA?

Hydrolyzed polymaleic anhydride (HPMA) is a low-molecular-weight polymer produced by polymerisation of maleic anhydride followed by hydrolysis to the diacid (polymaleic acid). Its very low molecular weight (~400–800 Da) is distinctive among water treatment polymers and is responsible for its most important property: exceptional thermal stability. While most polyacrylate and maleic/acrylic copolymer scale inhibitors degrade and lose performance above ~80–100°C, HPMA retains its scale inhibition activity at temperatures up to 200°C, making it uniquely suited for high-pressure boiler water treatment and high-temperature process water applications.

High-Temperature Scale Inhibition

In medium- and high-pressure boiler water systems (operating above 100°C steam temperature), HPMA is used to prevent calcium carbonate and calcium sulfate scale formation on heat transfer surfaces. Its superior thermal stability compared to conventional polymer inhibitors means it retains activity and does not itself thermally degrade into compounds that could contribute to boiler fouling. In high-temperature industrial process water circuits (pasteurisers, sterilisers, heat exchangers operating above 80°C), HPMA similarly outperforms standard water treatment polymers. It is effective at low dosages (5–20 mg/L) and is compatible with HEDP, DTPMP, and other phosphonate inhibitors used in boiler treatment programmes.

Cooling Water and Blended Applications

In cooling water systems, HPMA provides threshold scale inhibition for calcium carbonate, calcium sulfate, and calcium phosphate alongside dispersancy for suspended particulates. While its dispersant action is less effective than higher-MW polymers for large particle dispersancy, its superior thermal performance makes it the preferred polymer in high-temperature cooling circuits. Terracore Chemicals supplies HPMA as approximately 50% aqueous solution for water treatment programmes across Southern Africa.