衣康酸改性聚环氧琥珀酸的合成及其阻垢缓蚀性能的研究

目的为了拓宽聚环氧琥珀酸(PESA)的应用范围,合成了衣康酸改性聚环氧琥珀酸衍生物(IA-PESA),拟提高PESA的阻垢缓蚀性能。方法用顺酐合成环氧琥珀酸(ESA)和聚环氧琥珀酸(PESA),再利用ESA与衣康酸(IA)聚合制得IA-PESA,研究了IA-PESA的阻垢和缓蚀等综合性能。用FT-IR对PESA和IA-PESA进行表征。用黏度法测定了PESA和IA-PESA的分子量。结果在静态阻垢实验中,对CaCO_3阻垢率达到90%以上,对CaSO_4阻垢率高达95%,甚至100%。IA-PESA分散Fe(Ⅲ)和稳定Zn~(2+)性能明显好于PESA。在静态失重实验中,当IA-PESA与PESA的用量均为150 mg/L时,加IA-PESA的腐蚀速率明显小于加PESA的腐蚀速率。对钙垢和腐蚀试片的SEM研究表明,IA-PESA使致密度较高、晶格结构规整的CaCO_3和CaSO_4钙垢改变为致密度较低、疏松、形状不规整的晶型结构。IA-PESA使试片未发生均匀腐蚀和点蚀,表面光滑。结论在相同测试条件下,IA-PESA的阻垢、缓蚀、分散Fe(Ⅲ)和稳定锌性能都好于PESA,改变了设备表面钙垢的晶型结构,减少了垢下腐蚀,缓蚀作用明显。

Synthesis and Scale Corrosion Performance of Modified Polyepoxy Succinic Acid by Itaconic Acid

The work aims to extend the application range of polyepoxysuccinic acid (PESA) by synthesizing polyepoxy succinic acid derivatives (IA-PESA), so as to improve the anti-scale and corrosion performance of PESA. Epoxysuccinic acid (ESA) and polyepoxysuccinic acid (PESA) were synthesized by anhydride, IA-PESA was prepared by polymerization of ESA and itaconic acid (IA) and then the scale inhibition and corrosion inhibition properties of IA-PESA were studied. PESA and IA-PESA were characterized by FT-IR. The molecular weights of PESA and IA-PESA were measured by viscosity method. In static scale inhibition experiment, the scale inhibition rate to CaCO3 was over 90% above and that for CaSO4 was as high as 95% or even 100% under certain experimental conditions. The performances of IA-PESA dispersed Fe(III) and stable Zn2+ were significantly better than those of PESA. In static weightless experiments, when the dosage of IA-PESA and PESA were 150 mg/L, the corrosion rate of IA-PESA was significantly lower than that of PESA. From the results of SEM studies of calcium scale and corrosion specimens, CaCO3 and CaSO4 with high density and lattice structure were changed into loose and irregular crystal structure with low density by IA-PESA. The SEM of corrosion specimens proved that uniform corrosion and pitting had disap-peared and the surface was smooth. Under the same test conditions, the scale inhibition, corrosion inhibition, dispersing Fe(III) and zinc stabilization of IA-PESA are better than those of PESA. IA-PESA changes the crystal structure of calcium scale on the surface of the equipment and reduces the corrosion under the scale, thus playing a significant role in corrosion inhibition.