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主要研究工作及结论如下:1.稳态极化法研究测试结果表明:在该体系中不同浓度的PASP对碳钢表现出一定的缓蚀保护能力.PASP对碳钢腐蚀的阴、阳极反应能够同时起到抑制作用,但以抑制阳极反应为主;PASP在碳钢表面形成保护膜前后的阳极极化曲线有明显差异,存在吸、脱附过程,说明在该体系中PASP是以抑制阳极为主的吸附型缓蚀剂.最高缓蚀效率为浓度50<,g>/L时的86％.缓蚀效率还与体系温度、浸泡时间和金属表面状态有关.2.电化学阻抗技术测试结果表明:(1)常温下不同浓度的聚天冬氨酸在该体系中具有缓蚀作用,进一步证明了PASP是吸附膜型缓蚀剂,双电层电容与浓度的关系显示吸附过程遵循Langmuir规律.(2)一定浓度范围内,PASP的腐蚀抑制系数与浓度的关系是:logr=0.395+0.190 log C<,i>,缓蚀效率随着浓度的增加而增加,一定浓度后缓蚀效率趋于定值.最高缓蚀效率是浓度为50<,g>/L时的80.7％,与稳态极化法测试结果基本一致.室温16℃,浸泡2小时下,PASP在碳钢表面吸附作用的表观吸附常数为1.46(g/L)-1,饱和覆盖的双电层电容为4.12×10-5F.3.PASA与盐酸酸洗中普遍使用的传统缓蚀剂乌洛托品相比,在0.1-20g/L的浓度范围内,缓蚀效率基本相等.浓度均为20g/L时,PASP比聚合前的天冬氨酸单体缓蚀效率提高52.9％.4.PASP与I-离子有良好的正协同缓蚀作用,复配浓度比(PASP:I-离子)为20:1时就出现明显的正协同缓蚀效果.当PASP(浓度为2.5g/L)与I-离子比例为1:1时,协同缓蚀效率最高为82.7％,比单独使用PASP(5g/L)时提高52.7％;5.研究证明:PASP作为无毒、易生物降解的绿色缓蚀剂在盐酸中具有一定的缓蚀作用,有望成为酸性介质的绿色缓蚀剂.协同、复配可进一步提高缓蚀效率,减少用量,减低成本,将更具有实际意义.同时,实验得到了一些重要的电化学腐蚀参数,为今后研究PASP的缓蚀机理和性能提供有益的数据和规律参考.关键词:聚天冬氨酸 腐蚀缓蚀 碳钢 电化学阻抗 稳态极化盐酸 电化学Abstract With green Chemistry, green corrosion inhibitor should be nontoxic and its biodegradable. Polyaspartic acid (PASP), the Environmentally Benign corrosion scale inhibitor, which is nontoxic and its biodegradable, has become the focus of studying in the fields of chemistry, water treatment and medicine in the last decade. But the research into the effect of PASP on metal in strong acid with electrochemical method is rarely reported. In this paper we discuss the corrosion inhibition ability of PASP to 45＃ carbon steel in HCl solution with EIS method and stable polarity method. The primary results are as follows: 1 .The polarity curve measured with stable polarity method shows that, after PASP is added into 1mol HCl solution, it can inhibitate the reaction of cathode and anode, but the inhibition of anode is primary. The difference between the anode polarization curve and the curve in HCl solution is obvious. It lies in the absorbing process and desorption process. It proves that PASP as the absorbing inhibitor can inhibitate the anode primarily. The maximum inhibitor ratio is 86％. The temperature、 the immersing time, the station of the metal surface can influence the corrosion inhibition ratio.2. We measure the corrosion inhibition effect ofPASP on 45＃ carbon steel in 1mol HCl solution with electrochemical resistance method(1)At the normal temperature, the PASP of different density has certain corrosion inhibition ability. PASPproves further it belongs to the absorbing inhibitor or interface inhibitor. The relationship between the double layer capacitance and density shows that the dynamic absorbing processis consistent with the Langmuir absorption model. (2)The relationship between the corrosion inhibition coefficient and density is 1ogr=0.395+0.190 logCi. The efficiency increases with the increase of density. The maximum value of the corrosion inhibition efficiency in this experimentation is 80.7％ when the density is 50g/L, which is consistent with the result measured with stable polarity method. Immersed at room temperature for two hours, the apparent adsorption constant of PASP which is on the surface of Carbon steel is calculated to be 1.46 (g/L)-1 and the double layer capacitance is calculated to be 4.12× 10-5F when its surface is covered saturatly. 3.Comparedwiththe corrosion inhibitor Hexamethylenetetramine in HCl solution which has been widely used, PASP has the equal corrosion inhibition ratio within the scope of density of 0.1-20g/L. The ratio of PASP is 52.9％ higher than aspartic acid s inhibitor before it is polymerized. 4. PASP and I- have better positive (conjunct)function. When the density ratio is 20:1, there will come forth the positive (conjunction), and when the ratio is 1:1, the highter inhibition ratio is 82.7％,it will increase by 52.7％ over that when PASP is used alone. 5. The study proves that: as a secure and easily biodegradable green corrosion inhibitor, it will have certain corrosion inhibitionfunctions when it is used in HCl solution. It is likely to replace the traditional corrosion inhibitor that cant be decomposed biologically easily and the corrosion inhibitor which is poisonous, and it is likely to serve as the corrosion inhibitor in the HCl solution. complex、conjunction can further improve the corrosion inhibition ratio and decreasethe dosage . Some parameters obtained from the experiment will provide.Key Word:polyaspartic acid;corrosion inhibition;carbon steel;electrochemical impedance spectroscopy;stable polarity;hydrochloric acid;electrochemistry