Preparation And Characterization Of Polyaniline/Carbon Materials Conductive Composites

Polyaniline,as a conductive polymer,has high Faraday pseudopotential,low cost and simple synthesis process.It is a kind of polymer with excellent neutral energy and wide application range of conductive polymer.However,polyaniline also has some disadvantages such as insoluble refractory,poor stability,and these shortcomings limit its practical application.Graphene and other carbon materials have good electrical conductivity and stability,which can compensate for the low conductivity and poor stability of polyaniline.At the same time,introducing space stabilizers during the synthesis process can greatly improve the processability of polyaniline.The in-situ polymerization of polyaniline using low-temperature chemical oxidation can make a good composite with carbon materials.In this paper,polyaniline/graphite composites?SCCO₂-PANI/G?were prepared by in-situ polymerization using supercritical CO₂ technology.Polyaniline/graphene/carbon nanotube composites?PANI/Tr G/MWCNTs?were prepared by in-situ polymerization.Copolymerized polyaniline?m-PANI/PVP?was prepared by dispersion polymerization.The structure and electrochemical properties of the above composite materials were studied.Supercritical CO₂?10 MPa,50 oC?can strip natural graphite into nano-graphite sheets and disperse them evenly in polyaniline.When 5 wt% of graphite is added,SCCO₂-PANI/G composites with excellent electrochemical performance can be obtained.At a scan rate of 5 m V/s,it has a specific capacitance of 881 F/g.At a current density of 5 A/g,it has a specific capacitance of 672 F/g,and its interface transfer resistance is around 50 ?.Graphene and carbon nanotubes can build a dense conductive network,further enhancing their conductivity and stability in a polyaniline matrix.The results show that the addition of 100:2 carbon nanotubes at 7 wt% of graphene can effectively improve the conductivity of the material and the electrical conductivity can be improved by nearly one order of magnitude.At the same time,at a ratio of 100:2 graphene/carbon nanotubes,a material with high stability and relatively good specific capacitance can be obtained.At a current density of 5 A/g,the specific capacitance can reach 755 F/g.The transfer resistance is further reduced up to 5 ?.Space stabilizers can promote the copolymerization of two monomers in the copolymerization of aniline and 2-aminoterephthalic acid,and can make the product grow in a small spherical shape,preventing the aggregation of product particles.The dispersion and stability of the modified polyaniline?m-PANI/PVP?added with PVPK90 is better than that of the modified polyaniline?m-PANI?without PVP-K90,and the stability of the aqueous dispersion up to 600 minutes.The modified polyaniline prepared in this paper has multiple redox states of polyaniline,and the specific capacitance can reach 365 F/g at a scan rate of 5 m V/s.At the same time,since the modified polyaniline copolymer can be self-doped,m-PANI also exhibits good cycle stability.The polyaniline composite material prepared in this paper has good processing performance and electrochemical performance,and can be used in the fields of supercapacitors,flexible devices and so on.