Investigation of Chaotic Mixing for MWCNT/Polymer Composites

A chaotic mixer is developed and optimized in order to overcome challenges associated with mixing polymers with high aspect ratio nano-particulates. The chaotic mixing system utilizes two cylindrical rotors to uniformly mix multi-walled carbon nanotubes (MWCNTs) with a thermoplastic. Results of the electrical conductivity and electromagnetic interference (EMI) shielding effectiveness of the chaotic mixed nanocomposites were higher than ones mixed via a commercial HAAKE mixer. MWCNTs' length was investigated and it was observed that the MWCNTs in chaotic mixed nanocomposites are longer compared to HAAKE mixer. To investigate the effects of MWCNTs' length on the electrical properties, a 3D electrical model based on random walk method was developed and examined. Obtained results suggest that the chaotic mixer has a higher potential for mixing nano particulates into thermoplastics without breaking the nanotubes and improved electrical properties, compared to other types of melt mixing techniques.