Preparation And Characterization Of Conductive Polymer/MWCNTs Composites In Ionic Liquid

Conducting polymers possess the characteristics of the light weight, cheap, and easy processing.Their conductivity can be extended from the insulator to the semiconductor or conductor by thechemical or electrochemical doping. Carbon nanotubes possess the properties of low mass density,good conductivity，tenacity and stability, which enable them the ideal reinforcing agents forconducting polymers. In this paper, the common ionic liquid1-butyl-3-methylimidazoliumtetrafluoroborate （[bmim]BF₄） and the magnetic ionic liquid （MIL）1-butyl-3-methylimidazoliumtetrachloride ferric （[bmim]FeCl₄） were used as the dispersant of multi-walled carbon nanotubes（MWCNTs） and the polymerization medium. Many kinds of conducting polymer/MWCNTs（CP/MWCNTs） composites were successfully prepared. The specific processes were as follows:（1） Ball mill the MWCNTs and [bmim]BF4to prepare the gel [bmim]BF₄/MWCNTs, withinthem the MWCNTs was well dispersed by ionic liquid noncovalent functionalization. Then thepyrrole monomer was dispersed in the gel. Lastly, the oxidant ammonium persulfate （APS） was addto the gel to initiate the polymerization of the pyrrole monomer. The core-shell structurePPy/MWCNTs nanocomposites were successfully synthesized. The nanocomposite had a specificcapacitance （SC） of240F g^-1at a current density of0.2A g^-1and a capacitance degradation of12.7%after800cycles.（2） The MWCNTs was noncovalent functionalized by the [bmim]FeCl₄, then the MWCNTswas well dispersed in the gel. The3-methylthiophene monomer was added into the gel and in situpolymerized under the oxidation of FeCl₄-. The P-Meth/MWCNTs nanocomposites of the especialnanorods morphology were successfully synthesized via ball mill. The compositesP-Meth/MWCNTs prepared in [bmim]BF4initiated by the FeCl₃were also investigated. Themorphology of the P-Meth/MWCNTs prepared in two ionic liquids were different.（3） The P-3Meth possess better tensile strength, flexibility and stability, the PPy have the larger“theoretic SC”, they can compensated each other at some extent. In the [bmim]BF4, under the initiatedof APS, the PPy was polymerized on the P3-Meth/MWCNTs, the compositesPPy/P3-Meth/MWCNTs were successfully prepared by ball milling. The nanocompositesPPy/P-3Meth/MWCNTs had a capacity of216F g^-1at a current density of0.6A g^-1and acapacitance degradation of9.8%after1200cycles.