Synthesis and property study of a polyether tercopolymer scale inhibitor with carboxyl and sulfonic acid groups

Abstract A new environment‐friendly hydrophilic terpolymer of PAA‐AEO‐SAS was synthesized by free radical polymerization using acrylic acid (AA), aliphatic alcohol polyoxyethylene ether (AEO) and sodium allyl sulfonate (SAS). The structure and molecular weight were characterized by FTIR, 1 H‐NMR and GPC. The optimal monomer ratio, initiator level, reaction temperature and time for the synthesis of PAA‐AEO‐SAS were determined by the controlled variable method, and the inhibition performance on calcium carbonate (CaCO 3 ) scale at different water bath temperature, pH, Ca 2+ concentration and time were investigated by the static scale inhibition method. And the scales were analyzed by XRD and SEM. The results showed that the inhibitor had the best performance when the molar ratio of AA‐AEO/AA/SAS was 1:5:1, initiator was 4 mol%, the polymerization temperature was 85°C, and the reaction time was 2 h. Under the optimal synthesis conditions, the maximum inhibition efficiency was 90% (18 mg/L) and the M w and M n of PAA‐AEO‐SAS were 1546 and 1326, respectively. In addition, the surface morphology of calcium scale with the inhibitor was significantly changed from the characterization results. In short, the combination of multiple functional groups allowed the application of PAA‐AEO‐SAS in the complicated and challenging circumstances.