Highly conductive polymer composites from room-temperature ionic liquid cured epoxy resin: effect of interphase layer on percolation conductance

Abstract

An ionic liquid type imidazolium catalyst enhanced the conductivity of epoxy-anhydride resin based electrical conductive adhesives (ECAs) by more than two orders of magnitude compared with common imidazole compounds. Percolation growth dynamics study combining with epoxy curing kinetics results indicates that the enhancement of conductivity was attributed to the higher percolation efficiency within ionic liquid catalyzed ECAs. An “interphase layer” model was proposed to explain the percolation mechanism in the thermoset based conductive composite. The present work highlights the importance of cross-linking the polymer matrix with filler interconnections, and provides practical guidance on the control over percolation dynamics in conductive composites in order to achieve enhanced percolation conductivity.