Research On Preparation And Properties Of Conductive Polyaniline Film On Stainless Steel

Among conducting polymers the polyaniline,due to its cheap price,simplicity of preparation,favorable conductivity,unique doping mechanism and excellent stability.Its widely applied prospect is so good that it attracts more and more concern.One of the applications is corrosion protection for metals.Synthesized polymer coatings on the surface of metal,conducting polymer can inhibit corrosion process.Polyaniline is one of the most studied conducting polymers.In recent years,it has some reports about synthesis of conductive polyaniline film around the world,but the synthesis mainly used in electrochemical methods.Recently,it is interested in in-situ polymerization method.This method don't need special equipment,it works simply,the thickness of polyaniline films could be controlled.In principle,polyaniline film could be synthesized on almost any surface of substate by in-situ polymerization method.It has many research reports about synthesis of conductive polyaniline film on the glass,fibre,polymer by this method,but synthesis of conductive polyaniline film on the metallic surface has not been studied.Because of this reason,conductive polyaniline films were synthesized on stainless steels by in-situ polymerization method and constant potential method in this paper.And the research results can be summarized as follows:(1)Conductive polyaniline films were synthesized on stainless steels by two methods,and the optimal synthetic technics were obtained.(2)The corrosion resistance of conductive polyaniline films were studied by chemical corroding proof,electrochemical anodic polarization curves and electrochemical impedance spectroscopy.The influence of synthetic conditions on corrosion resistance of conductive polyaniline films were discussed.The results show that corrosion resistance of stainless steels which were covered by polyaniline films were increasingly improved.(3)The influence of synthetic conditions on conductivity of polyaniline films were studied.The results show that synthetic conditions had biggish influence on conductivity of polyaniline films.(4)The component functional group and corresponding configuration of conductive polyaniline films were discussed by FTIR,The results of XRD analysis show that conductive polyaniline films were composed of crystals.(5)Morphology of conductive polyaniline films by SEM were observed,the results show that conductive polyaniline films which were synthesized by the two methods were composed of particles.The results of EDS analysis show that SO42- entered into polyaniline conjugated chain,and it's possible that metal-oxide film formed on stainless steel due to doped polyaniline.(6)The synthetical mechanism and corrosion resistance mechanism of conductive polyaniline film on stainless steel were discussed.