Shell structure control of monodisperse polystyrene‐silver composite microspheres and synthesis of epoxy resin‐based anisotropic conductive adhesives

Abstract Monodisperse polystyrene‐silver (PS‐Ag) composite microspheres were used to enhance the electrical conductivity of epoxy resin‐based anisotropic conductive adhesives (ACAs). Specially designed PS‐Ag composite microspheres were used as conductive elements to construct anisotropic conductive arrays. In addition, the surface microstructure and morphology of PS‐Ag composite microspheres were controlled by adjusting the silver precursor concentration and implemented electroless plating method. The size and conductivity of the final composite microspheres used for ACAs were 2.572 μm and 81,967 S cm−1, respectively. In addition, diglycidyl ether of bisphenol‐A (DGEBA) epoxy resin and polyamide resin were used as the matrix resin and curing agent, respectively, to predict the optimum curing process parameters based on curing kinetics. Based on this premise, carboxyl‐terminated butadiene‐acrylonitrile (CTBN) and PS‐Ag composite microspheres were used as the toughening agent and conductive filler, respectively, and a facile strategy was developed to prepare ACAs (viz., PS‐Ag/Ep‐ACAs). As the PS‐Ag composite microspheres exhibited a submicron structure, PS‐Ag/Ep‐ACAs creatively exhibited satisfactory anisotropic electrical and mechanical properties. Therefore, the research strategy and fabrication methods proposed demonstrate immense potential for the fabrication of large‐scale ACAs in practical applications.