Preparation and properties of conductive polymer doped with Ag-coated glass fiber for EMI shielding

In this study, based on the conductive polymer filled with Ag-coated Cu dendritic powder (ACDP), Ag-coated glass fiber powder (AGFP) was selected as assistant filler to improve the conductive network. The results showed that the volume resistivity reached 0.004Ω·cm when the total fillers were less than 70.6 wt%. The effect of the filler content of the AGFP powder on the conductivity, creep behavior of resistance and piezo-resistivity properties of the conductive polymer was studied. Under constant pressure, the resistance creep behavior of the conductive polymer showed that the volume resistivity decreased nonlinearly with time. When the pressure was applied within 0-2.0MPa, the conductivity variation of the conductive polymer exhibited a positive pressure coefficient of resistance (PPCR). However, the piezoresistance effect could be neglected with increasing filler content and applied pressure. In addition, the reliability of the conductive polymer under aging at 85°C and 85% relative humidity (RH) in a temperature/humidity chamber was discussed.