Synthesis of Aspartic Acid/citric Acid Copolymer and Its Anti-scaling and Inhibition Performance

Poly (citric acid/aspartic acid), P(CA/ASP) was prepared by thermal polycondensation method. The synthesized copolymer P(CA/ASP) was characterized by FT-IR spectra and size exclusion chromatography (SEC). The scale inhibition performance of P(CA/ASP) against CaSO₄ was evaluated by static scale inhibition method, and the inhibition ratio of P(CA/ASP) was studied by electrochemical method. The results show that the molar ratio of reaction reagents (citric acid and aspartic acid) was 1:1 (product C), the scale inhibition rate against CaSO₄ was up to 97%. The inhibition performunce of product C is good. When the concentration of product C in 3.5% sodium chloride solution was 200 mg/L, the corrosion inhibition rate for copper could reach 81.6%. P(CA/ASP) has excellent scale inhibition performance against CaSO₄ and corrosion inhibition performance for copper.