Synthesis And Application Of New Type Of N-containing Organic Corrosion Inhibitors

Metal corrosion is playing an important role in national economy.Although it is inevitable,it can be slowed down or prevented.At present,the main anti-corrosion technologies of metal include applications of corrosion resistance materials,surface anti-corrosion technology,added corrosion inhibitors,and electrochemical protection. And the added corrosion inhibitor is a simple,inexpensive and applicability of the anti-corrosion methods.In many corrosion inhibitors,the most practical corrosion inhibitors is the inhibitors whose configuration has N,O,S,P which can provide solitary electronic or have the activity molecules which have unsaturated bonds.The corrosion inhibitors which have N-containing are studied most in recent years.In this paper,we synthesized 5-phenyl-4-amino-triazole thione(PAMT) and water-soluble polyaniline copolymer with acid-dope.And the inhibitive performances of them were studied through weight loss and electrochemical.In this paper,5-phenyl-4-amino-triazole thione(PAMT) was synthesized by three steps.The influencing factors of synthetical condition were analyzed,and we acquired the optimization condition of the preparation.Using FT-IR to analysis the structure of PAMT,We tested the inhibitive performance of PAMT to carbon steel by weight loss in HCl(10%) and the inhibition efficiency can reach to 92%.And we tested the inhibitive performance of PAMT to stainless steel by electrochemical and the inhibition efficiency can reach to 84%.We discussed the corrosion mechanism of PAMT and regard the inhibitor of PAMT as the mixed-type corrosion inhibitor which was mainly to control the anode.In this paper,aniline and its derivatives were used to synthesize water-soluble polyaniline copolymer with HCl-dope or HAc-dope.The optimal condition of the preparation of water-soluble polyaniline was carried out by weight loss.Using FT-IR to analysis the structure of water-soluble polyaniline.The inhibitive performances of water-soluble polyaniline to carbon steel were tested by weight loss in 10%HCl and the inhibitive performance of water-soluble polyaniline to stainless steel by electrochemical in 1mol/L HCl.We educed when the dosage was 3%,E_corr of water-soluble polyaniline with HCl-dope was -0.432V and E_corr of water-soluble polyaniline with HAc-dope was -0.433V.Through the potentiodynamic polarization curves,we educed that the inhibitor of water-soluble polyaniline with HCl-dope was the mixed-type corrosion inhibitor which was mainly to control the anode,but the inhibitor of water-soluble polyaniline with HAc-dope was the anode-type corrosion inhibitor.The cinnamic aldehyde was an environment friendly corrosion inhibitor.It has a good inhibitive performance,but because of the high cost,the use of cinnamic aldehyde was restricted.The synergistic inhibition effect of the cinnamic aldehyde and the synthesized inhibitors were investigated by electrochemical,when the the dosage of corrosion inhibitor was 0.5%in 1mol/L HCl solution,we educed when the quality proportion of PAMT and cinnamic aldehyde was 8:2,the inhibition efficiency of corrosion inhibitor to stainless steel was 94%.And when the the dosage of water-soluble polyaniline was 1.5%and the quality proportion of water-soluble polyaniline and cinnamic aldehyde was 6:1,the inhibition efficiency of corrosion inhibitor to stainless steel in 1mol/L HCl was 90%.