Conductivity of diblock copolymer system filled with conducting nano-particles: Effect of copolymer morphology

We explore the effect of temperature-induced morphological changes in insulating diblock copolymer system (DBC) filled with conductive fillers on the conductivity of this composite. By making use of the developed method that relies on the consistent phase-field model of DBC, Monte-Carlo simulations of the filler distribution in DBC, and resistor network model, we quantitatively relate the morphology of filled DBC and its conductivity. In particular, we demonstrate that the order–disorder transition between the random and ordered microphases of DBC causes the conductor-insulator transition in the network of conductive fillers immersed in this system. The order–order transition between the ordered lamellae and cylindrical microphases of DBC is found to co-occur with a jump in the composite conductivity caused by restructuring of the conductive filler network.