Purified Single-walled Carbon Nanotubes In Arc Discharge Method And Its Modified Styrene-butadiene Rubber

Because of their unique structure and significant advantages, such as strong mechanical properties, high thermal stability, electrical and magnetic properties, carbon nanotubes have attracted considerable attention since being discovered. The novel 1-D nanometer size with high tensile strength and modulus makes SWNTs a good candidate for producing reinforced composite with various matrics.This study was focused on the purification of arc-SWNTs and the application of SWNTs as reinforcement for SBR. A wet chemistry procedure which coupled HNO₃ oxidation and a dispersion-centrifugation cycle was applied to the dissolution and purification of as-prepared arc-SWNTs. It was validated that HNO₃ oxidation treatment effectively removed most of the amorphous carbon and metal particles, and generated little hydrophilic group such as carboxyl and hydroxyl on the surfaces of SWNTs. The soluble sample was fractionated via a dispersion-centrifugation cycle, carbon nano-particles were removed and highly pure and well-separated SWNTs were successfully obtained in the middle fraction. SWNTs reinforced the mechanical properties of SBR obviously. The SWNTs/SBR composite with 1wt% SWNTs exhibited the best mechanical properties. Comparing to pure SBR, its tensile strength improved by 54%, M₁₀₀ and rigidity were reinforced respectively by 30% and 15%. It was also found that small amount of SWNTs accelerated the degradation temperature of SBR and therefore they improve the stability of SBR in air.