Preparation And Properties Of High Conductive Powders Modified By Pyrogallol-Ferric Ion

The development of electronic and electrical industry is more and more rapid,electromagnetic radiation pollution is becoming more and more serious.It is more and more important to use electromagnetic shielding materials to effectively suppress electromagnetic wave radiation.Conductive polymer materials consisting of conductive fillers and polymer matrix are one of the major categories of electromagnetic shielding materials.The performance of conductive fillers is the key to the electromagnetic shielding performance of materials.Composite conductive filler is one of the most widely used conductive fillers because of its excellent conductive properties,low density and low cost.However,at present,there is little research on composite conductive fillers in China.Most of the demand in the market comes from imports.Therefore,the research and development of composite conductive fillers with high conductivity is very important.Pyroglucinol and ferric ion can rapidly form a triploid chelate with adhesion property and deposit on the surface of the matrix,thus improving the binding force between metal particles with the matrix.This method is not only simple to operate,green and environmentally friendly,but also cheap,and more suitable for industrial applications.Based on the above viewpoints,pyrogallol-trivalent iron ion modified composite conductive fillers were prepared in this paper.The specific conclusions are as follows:(1)Silica microspheres(SiO2)were successfully modified by pyrogallol(PG)and trivalent iron ions(Fe3+)complex deposition on the surface of SiO2.The optimum deposition conditions are as follows:pH=8.5,Fe3+concentration is 0.16 g/L and deposition time is 1 min.Silver-plated silica microspheres with conductivity up to 1000S/cm were prepared by electroless silver plating on silica microspheres modified by pyrogallol-trivalent iron ions.The whole process is green,environmentally friendly,simple to operate and low cost.It has a certain industrial application prospect.(2)Silver-plated graphene oxide(GO)modified by pyrogallol-trivalent iron ion was prepared by "two-step" silver plating with "nucleation first,growth second" method.The conductivity of GO was as high as 10 000 S/cm.This"two-step" silver plating method is more suitable for the matrix which is difficult to be plated on the surface.It provides a new method for preparing composite conductive fillers.