Conductivity Properties Of Modified Polyacrylonitrile/Multiwalled Carbon Nanotube Composites

Polymer/carbon nanmotube composites, with the merits of carbon nanotubes and polymer demonstrated excellent performance in mechanical, electrical, optical and thermal, is considerde as a very promising new compoundmaterials.In this thesis, PAN as the substrate, MWNTs as the doped body prepared PAN/MWNTs composites. The electrical conductivity of the composites was improved after modified by heat-treated, we studied the structure, performance, and interaction of the modified PAN and PAN/MWNTs. Including the following aspects.1. Study of the modified conditions of PANThe heat-modified mainly in two ways. The first PAN was dealed in same temperature with different times. Second PAN was modified by different temperature in the same time. These two operations were conducted in air atmosphere and vacuum atmosphere respectively.FTIR results showed that the degree of cyclization is increased after modified. Founding the degree of cyclization of PAN modified in air atmosphere is higher than in vacuum atmosphere. NMR results showed that the structure of PAN was changed after modified, part of the nitrile (-C=N) is transtormed to the imine (-C=N)MWNTs and fMWNTs which was treated in nitric acid, were blended with PAN. The conductivity of PAN/MWNTs is higher than PAN/fMWNTs.2. The electrical properties of modified polyacrylonitrile multi-walled carbon nanotube composites.FTIR, UV-VIS, Raman, XPS and other means to expolre the structure of the composites before and after modification. The results showed that the conjugate ring system which was formed after PAN heat-treated enhanced the interaction with MWNTs. Produced a larger conjugate ring system. The electron has a greater delocalization, increased carrier migration rate and improved the conductivity of the compisites. The electrical properties of modified PAN/MWNTs improved two orders.