Abstract:

Using silver coated glass microsphere composite particles(Ag/GM) synthesized by liquid chemical reduction method as raw materials, and ethylenediamine as surface modification agents, Ag/GM with ethylenediamine on their surface were prepared and used as conductive fillers to fabricate electrically conductive adhesive. Compared with the Ag/GM synthesized by chemical reduction method and modified with boiling water, the Ag/GM modified with ethylenediamine are dispersed in the epoxy adhesive more effectively and the interface energy between them and epoxy resin matrix is reduced because of the formation of the chemical bonding between the epoxy resin and the ethylenediamine adsorbed on the surface of Ag/GM. The as-fabricated electrically conductive adhesives show a relative high conductivity and low conductive percolation threshold, which is reasonably explained by the conductive percolation theory and equivalent circuit diagram. The result provides a simple and effective way to improve the conductivity of electrically conductive adhesive.

Key words: Ethylenediamine, Silver coated glass microsphere core-shell composite particle, Electrically conductive adhesive, Conductive percolation threshold, Interface effect