Study On Synthesis Method And Scale Inhibition Performance Of Aspartic Acid - Serine Copolymer

The aim of this paper was to resolve the problems of the high reaction temperature and long reaction time of the traditional solid-phase polymerization. In this paper, the process of synthesis, scale inhibition and mechanism were studied in detailed.The appearance of the crystal, the crystallinity, and the yield were evaluated as the standard to select the optimum pre-treatment conditions. First, optimized cyntheis process of PA-S. Second, analyzed the characteristics of products. Third, investigated the influence of reaction conditions on yield, molecular weight and sacle inhibition rate of PA-S. In addition, the realationship between molecular weight and scale inhibition rate of PA-S were analyzed.The results showed that the lower crystallinity, the smaller partical size and yield. By comparation, solution evaporation method was chosed for optimal recrystallization. The optimum thermal polycondensation conditions were that mass percentage of L-serine was10%, reation temperature was200℃, reaction time was4.0hours. Under the optimum conditions,95%PA-S, yield ratio and93%scale inhibition rate to calcium carbonate could be reached, respectively. Compared with traditional solid phase polymerization, the temperature decreased40℃. However, the scale inhibition rate increased3%and the yield increased23%. PA-S scale inhibitor optimum process conditions were that the dosage of PA-S was9mg·L-1, constant time was6hours, solution temperature was20℃, the concentrate of calcium was50mg·L-1, more than98.51%scale inhibition rate to calcium carbonate was obtained.PA-S could control the precipitation of calcium carbonate by the regulation of crystal transformation. When the concentration of PA-S was10.0mg-L"1, the content of vaterite was higher. Because the interaction of different types among CaCO3precipitation, inhibited the further growth and precipitation particles, which could reduce the diameter of precipitation and achieve the purpose of scale inhibition, When the temperature of solution was80℃, the diameter of precipitation could reach up to0.5μm.