Properties investigation on electrically conductive adhesives based on acrylate resin filled with silver microsheets and silver plating carbon fibers

Abstract

The introduction of highly electrically conductive fillers (Ag microsheets and silver plating carbon fiber) can functionally improve the electrical conductivity of acrylate resin. In this study, Ag microsheets and Ag/CF were thus introduced into acrylate polymer via solution blending method under ultrasonication in order to improve the electrical conductivity of the acrylate resin. The properties and microstructures of Ag microsheets, CF, Ag/CF and ECAs were performed by scan electron microscope (SEM), X-ray diffraction analysis (XRD), etc. SEM images and XRD results illustrated that the impurities in carbon fiber could be completely removed after the adequately alkali treatment. The SEM images showed that large numbers of metallic silver particles were uniformly and densely coated on the surface of the carbon fibers and hybrid fillers (silver microsheets and Ag/CF) could homogeneously disperse in acrylate resin. Electrical conductivity measurements demonstrated that the electrical conductivity of ECAs increased with the increasing content of hybrid fillers and the percolation threshold of ECAs was 5 wt%. The electrical conductivity of ECAs at its percolation threshold was 15.79 S/cm, which was two orders of magnitude higher than that of the ECAs based on acrylate resin filled with silver microsheets. The increment in Ag/CF contents may decrease 180° peel strength and raise shear strength with low content of Ag/CF. The overall performance of ECAs was optimum with 2 wt% Ag/CF. The TGA analysis indicated that ECAs possess excellent thermal stability.