polyaspartic acid sodium salt  is a kind of biopolymer materials, of which molecules contains abundant amido bond, carboxyl and other active groups. Amido peptide bond has biological activity and high chemical stability, hard to decompose at high temperature; carboxyl group can be complex with many metal ions in water, which make polyaspartic acid sodium salt  have high chemical activity in aqueous solution; in each structural unit of PASP, the oxygen and nitrogen atoms can easily form hydrogen bonds with water molecules, it has good hydrophilicity and water solubility. The special molecular structure of PASP ensures that it has good dispersing ability, corrosion inhibiting properties, excellent biodegradability and environmental friendly characteristics.