Preparation And Properties Of Metal-doped Polyaniline/SEBS Conductive Elastomer

Conductive elastomer can be made by filling conductive material into insulating elastomer matrix,leading to obtain composite materials with both conductive and elastic deformation properties.With the development of organic electronic industry,people are more and more interested in developing new conjugated polymers for various electronic devices.Polyaniline(PANI)has attracted much attention due to its unique physical and chemical properties such as ionic and electronic conductivity,redox activity,heat resistance and chemical resistance,low cost and easy conversion of monomer into polymer.Unfortunately,the poor solubility of PANI in typical organic solvents greatly limits its practical application.One of the most promising methods to overcome this problem is to introduce various substituents such as alkyl,alkoxy,sulfo and other functional groups into the polymer chain Relevant studies have shown that the groups of PANI derivatives improve the processability of the polymer.Therefore,the preparation of PANI with solubility in common solvents and the construction of effective conductive paths are very important for the preparation of conductive elastomers,which is a hot issue.In this thesis,potassium permanganate(KMnO4)was used as an oxidant for the oxidative polymerization of anilines,and the conductive PANI was synthesized in two different oxidation systems by chemical oxidation and emulsion polymerization extraction method.The conductive PANI was then combined with thermoplastic elastomer styrene styrene butadiene styrene(SEBS).Later,the conductivity of the conductive elastomer was improved by doping silver particles.Flexible composites with large deformation were prepared.The main research contents are as follows(1)In the oxidation system of KMnO4,inorganic acid hydrochloric acid was doped to prepare potassium hydroxide Mn@PANI.In order to improve its physical solubility,DBSA was prepared by emulsion polymerization extraction method instead of hydrochloric acid with organic acid.Mn@PANI,PANI(APS)solution was prepared in the system of ammonium persulfate(APS)oxidation.PANI/SEBS conductive elastomer was prepared by mixing three kinds of PANI with thermoplastic elastomer SEBS in the ratio of 3:7 and volatilizing solvent.In this paper,the effects of two different oxidation systems on the solubility and conductivity of PANI were investigated.The product was characterized by some test methods.The results showed that the solubility of PANI solution prepared by oxidation with KMnO4 was greatly improved in comparison with that prepared by APS oxidant system,but the conductivity was slightly inferior.(2)The PANI/SEBS conductive elastomer prepared by soluble PANI was doped.The Ag/PANI/SEBS conductive elastomer was prepared by mixing PANI toluene solution with thermoplastic elastomer SEBS toluene solution.The Ag/PANI/SEBS conductive elastomer was prepared by doping the silver particles in a certain proportion and volatilizing the solvent.The results showed that the conductive properties of PANI/SEBS conductive elastomer were improved by adding silver particles.And with the increase of doping amount,the conductivity was also gradually improved.However,too high doping content resulted in adverse effects on its mechanical properties.(3)The mechanical properties of Ag/PANI/SEBS conductive elastomer were tested.When the content of Conductive PANI was 30.00 wt%,the conductive elastomer composite not only possessed good conductivity,but also had the elongation at break at about 700%,In addition,good reversibility and stability were observed in the initial ten cycles under different strain ranges and tensile rates.