Rheological behaviors of the multi-wall carbon nanotubes/polyethylene composites prepared by a master batch method

In this work, the rheological properties of four multi-wall carbon nanotubes (MWCNTs)/polyethylene (PE) composites containing 1 wt.% (mPEC1), 3 wt.% (mPEC3), 5 wt.% (mPEC5), and 10 wt.% (mPEC10) MWCNTs prepared by the masterbatch method were investigated and compared with those of the pure PE. The rheological investigation includes strain sweeping, frequency sweeping, stress relaxation behavior, yield stress, characteristic relaxation time, temperature effect on linear viscoelastic behavior, and gel behavior. It is mainly found that (1) the MWCNTs-MWCNTs interaction resulting in MWCNTs network structure in the PE matrix and the MWCNTs-PE interfacial interaction increase the storage and loss moduli of the MWCNTs/PE composite in comparison with those of pure PE; (2) the time-temperature equivalence principle is applicable only for pure PE and mPEC1; (3) for gel behavior of MWCNTs/PE composite at 160-180 degrees C, the phi g value decreases with the increase of temperature and the highest Sg value is obtained at 170 degrees C.