两种甲基丙烯酸二甲氨乙酯基季铵盐的合成及缓蚀性能

以甲基丙烯酸二甲氨乙酯为母体，分别以氯丙烯和氯化苄为桥连基设计合成了两种季铵盐（DMA-1和DMA-2）。利用红外光谱、核磁共振氢谱证实了所得产物与设计相一致。再依次通过失重实验、电化学实验、AFM、接触角等手段测试了Q235钢在含有DMA-1 和DMA-2的1mol/L盐酸中的缓蚀性能，探讨了其在Q235钢表面的吸附和缓蚀机理。结果显示：在较高温度下，DMA-1和DMA-2仍能牢固吸附在Q235钢表面，当所加入缓蚀剂的浓度为100 mg/L 时，缓蚀率均可达92.7%以上，显示出良好的缓蚀性能，且 DMA-1比DMA-2具有更好的缓蚀效果。热力学计算结果表明DMA-1和DMA-2在Q235钢表面的吸附是化学吸附，过程自发、放热，且符合Langmuir等温吸附，属于良好的阳极型缓蚀剂。量子化学计算结果表明了DMA-1更容易提供或接受电子，进一步研究了DMA-1和DMA-2的分子结构与活性位点。

Synthesis and corrosion inhibition Performance of two 2-(Dimethylamino)ethyl methacrylate quaternary ammonium salts

2-(Dimethylamino)ethyl methacrylate has excellent properties of non-toxicity and degradability, but little research has been done on the direction of corrosion inhibitors. In this paper, two kinds of quaternary ammonium salts (DMA-1 and DMA-2) were synthesized by using 2-(Dimethylamino)ethyl methacrylate as the matrix and chloropropene and benzyl chloride as bridging groups. The obtained product was con-firmed to be consistent with the design by infrared spectroscopy and nuclear magnetic resonance spec-troscopy. Then, the corrosion inhibition performance of Q235 steel in 1 mol/L hydrochloric acid contain-ing DMA-1 and DMA-2 was tested by weight loss experiment, electrochemical experiment, AFM and con-tact angle. And their adsorption and corrosion inhibition mechanisms on the surface of Q235 steel were discussed. The results show that at higher temperatures, DMA-1 and DMA-2 can still be firmly adsorbed on the surface of Q235 steel, and when the concentration of corrosion inhibitor added is 100 mg/L, the corrosion inhibition rate can still reach 92.7% or more. So it shows good corrosion inhibition performance, and DMA-1 has better corrosion inhibition effect than DMA-2. The thermodynamic calculation results show that the adsorption of DMA-1 and DMA-2 on the surface of Q235 steel is chemical adsorption, the process is spontaneous and exothermic, and it is consistent with Langmuir isotherm adsorption. It is a good anode type corrosion inhibitor. Frontier chemical calculations show that DMA-1 is easier to provide or accept electrons, and further study the molecular structure and active sites of DMA-1 and DMA-2.