Lubricants of silver fillers for conductive adhesive applications

Electrically conductive adhesives (ECAs) are composites of polymer matrices and conductive fillers. Silver (Ag) flakes are widely used as fillers for conductive adhesives. Generally, there is a thin layer of organic lubricant residue on the commercial Ag flake surface. This lubricant layer influences rheology, conductivity and other properties of ECAs. The nature of the lubricant on a Ag flake and the interaction between the lubricant and the Ag flake surface were studied by diffuse reflectance infrared spectroscopy (DRIR). Thermal decomposition of the lubricant was studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). In addition, the effects of some chemical compounds on lubricants were also investigated and are reported in this paper.