Phase structure, rheology and electrical conductivity of co-continuous polystyrene/polymethylmethacrylate blends filled with carbon black

In this work the effect of carbon black concentration on the rheology, electrical conductivity and morphology development of PS/PMMA co-continuous blends during quiescent annealing is investigated. In the blends studied carbon black is preferentially localized in the PS. The specific interfacial length, which is taken as a measure of fineness of blends morphology, increases linearly with the carbon black content in the blends after melt mixing. However, significant suppression of the structure coarsening during annealing is observed in systems with more than 3 vol.% of carbon black, in which the filler structures induce pronounced flow restrictions. The final change in the flow behaviour of the blend induced by annealing is a result of competition between morphology coarsening and particle structure formation and it depends on the concentration of carbon black.