Conductive and viscoelastic behaviors of carbon black filled polystyrene during annealing

Aggregation of carbon black (CB) aggregates in polystyrene melt was traced by simultaneous measurement of resistance (R) and dynamic storage modulus (G′) as a function of annealing time. There existed a dynamic resistance percolation in the time evolution of R while G′ increased gradually during the whole experimental time scale. Dynamic resistance and modulus percolation models were used to model the time-dependent R and G′, respectively. Furthermore, the time evolution of G′ was explained with a combination of the kinetic cluster–cluster aggregation model and the first order kinetics aggregation model. It was found that the aggregation of CB aggregates in the molten polystyrene has a close relation with the terminal relaxation of polystyrene molecules. The results indicated that the interfacial tension between polystyrene molecules and CB plays a crucial role in driving CB to aggregate.