Generally, polymaleic anhydride has a relative molecular weight of 400 to 800, while polymaleic anhydride using solvent method (PMA-s) has an average molecular weight of about 1000. Because PMA-s is based on polymerization and hydrolysis of maleic anhydride in the solvent phase.
Maleic anhydride has good solubility in organic solvents due to the principle of similar compatibility. Maleic anhydride can be well polymerized into long chain polymaleic anhydride in organic solvent. Polymaleic anhydride (PMA-s) prepared by the solvent method has a high molecular weight, but a loose structure, resulting in low density. In contrast, water is a polar solvent, maleic anhydride in water can not form long-chain polymaleic anhydride, but the polymaleic anhydride formed (PMA-w) has a compact structure and high density.
The polymaleic anhydride solvent method (PMA-s) and the polymaleic anhydride hydrolysis method (PMA-w) are different not only in molecular weight and density but also in scale inhibition and dispersion effect.
The Polymaleic anhydride solvent method (PMA-s) has a better effect in water treatment, especially when the dosage is low.
|Item||Polymaleic Anhydride water method (PMA-w)||Polymaleic Anhydride solvent method (PMA-s)|
|Appearance||Light yellow to brown red transparent liquid||Amber liquid|
|Solid content, %||48.0 Min.||48.0-52.0|
|Bromine value, mg/g||80 Min.||—|
|pH value (1% aqueous solution)||2.0-3.0||—|
|Density (20℃), g/cm3||1.22-1.25||1.16-1.22|
|pH value (stock solution)||—||2.0 Max.|
Polymaleic anhydride (PMA-s) still has good scale inhibition and dispersion effect on carbonate below 300 ℃. The scale inhibition time can reach 100 hours. Because of its excellent scale inhibition and high-temperature resistance, HPMA-s is widely used in flash distillation devices of seawater desalination, low-pressure boilers, steam locomotives, crude oil dehydration, water and oil pipelines, and industrial circulating cooling water.
Polymaleic anhydride (PMA-s) can also be used as the main component of advanced cleaning agents. It can be used as a rinsing agent for textiles to reduce the ash content of textiles. In addition, the agent has a certain corrosion inhibition effect and has a better effect when compounded with zinc salt. PMA-s can also be used as a cement admixture and a saline-alkali soil conditioner.
When HPMA-s is used alone, the concentration is generally 1~15 mg/L, and it is often used in combination with organic phosphonates, which has good compatibility. Polymaleic anhydride has good compatibility with organic phosphonic acids and quaternary ammonium salts and is not affected by chlorine and other oxidizing biocides under normal use conditions. It will not cause environmental pollution.
200L plastic drum,IBC(1000L),customers’ requirement. storage for one year in a shady room and dry place.
Acidity, Avoid contact with eye and skin. Once contacted, flush with water.