Hollow glass beads, high temperature, corrosion resistance, low creep, good quality of light and chemical stability, excellent mechanical properties and thermal physical properties, get in the building materials, plastics, rubber, paint, and other fields are widely used. Through the hollow glass microspheres surface modification, plated with a layer of metal that can make it conductive or electromagnetic wave absorption performance.
Chemical plating method in the surface of hollow glass microspheres silver plated layer of metal, it is possible to have good conductivity, the conductive rubber can be used as an electromagnetic shielding conductive filler.
The pretreatment of hollow glass microspheres configured dope also added, adding an appropriate amount of dispersant, and then adding silver ammonia solution, the reaction was stirred 20min, deionized water to drink alcohol to clean the glass beads, and drying.
After Pretreatment with three silver-plated hollow glass microspheres were obtained spectrum detection, removal of a small atomic number elements and trace impurity elements.After analysis, the "three-step" Silver content obtained after pretreatment silvered hollow glass microspheres obtained the silver content is lower than after the other two pre-treatment process, the "silver ammonia solution activation method" and "colloidal palladium law "after pretreatment silver content obtained silvered hollow glass microspheres closer, respectively, 65.44% and 60.38%, have reached a high silver content, the silver content, the latter two pretreatment process better than the "three-step", while in the "three-step" to use to hydrofluoric acid and other toxic substances .A certain amount of silver-plated hollow glass microspheres into the inner diameter of 2.1㎝ mold under pressure 5t pressed into a thin disk of uniform thickness sample, the four-probe resistivity tester.Consistent with resistivity and spectrum analysis results obtained by three processes silvered hollow glass microspheres.
After three Pretreatment results obtained silver-plated hollow glass microspheres of SME's. It can be drawn from the experiment. After "three-step" spot coating surface obtained after pretreatment silvered hollow glass microspheres more explanation did not form a continuous coating;After "Silver ammonia solution activation method" and "colloidal palladium Law" spot pretreatment coating surface obtained little silver-plated hollow glass microspheres, coating is smooth, indicating that the use of "colloidal palladium Law" and "Silver ammonia solution activation method "preprocessing can prepare high silver content, coating evenly silvered glass beads, the reason is the quality of hollow glass microspheres smaller, limited floating in the solution of the upper layer, the contact area with the pretreatment solution,The "three-step" pre-treatment process step more, each step will bring some loss, so get a lower content of silver and silver-plated hollow bead coating uneven."Silver ammonia solution activation method" and "colloidal palladium Law" On the one hand is "sensitizing and activation" step, reducing the losses and the impact of Step by Step; on the other hand, "silver ammonium activation method" is used as an activator point, "colloidal palladium law" is used palladium as active sites, which makes it easier for the silver particles deposited on the surface of hollow glass microspheres, so after "silver ammonium activation method" and "colloidal palladium law" prepared by plating pretreatment silver plated surface of hollow glass microspheres are more uniform, smooth.