A study on rheological behavior of multi-walled carbon nanotubes (MWCNTs) filled polystyrene (PS) melts submitted to isothermal annealing at temperatures from 170℃ to 190℃ was carried out.It is found that the filled PS melts with different volume fractions () of MWCNTs from 0 to 0.05 underwent dynamic modulus percolation (DMP) during isothermal annealing and the DMP behaviors followed time-temperature superposition (TTS) principle disclosed for the first time.The filled melts with below percolation threshold exhibited liquid-like viscoelasticity during annealing

and the activation energies (EG' and EG) of the dynamic storage modulus (G') and loss modulus (G) were higher and lower than that of viscous flow (E) of pure PS melt

respectively

but were in agreement with the dynamic modulus activation energies of dynamic moduli of PS melt at the same frequency as that used in DMP test

the dynamic moduli were obtained through the dynamic frequency experiment.Annealing the melts having above percolation threshold caused MWCNTs to aggregate further so much as that the melts changed from the liquid-like to the solid-like.In this case

both EG' and EG were smaller than E while energies (Et' and Et) of liquid-like to solid-like transition were significantly higher than E.Moreover

the activation energies of dynamic modulus exhibited a sharp decrease in the percolation transition region.It was suggested that the isothermal time-dependent DMP was closely related to the formation of the MWCNTs aggregation-induced construction of three-dimensional elastic network while the terminal relaxation of PS macromolecules was not the determinant factor for DMP.