Different Surfactants Affect the Dispersion of Nano Silver Powder

Nano-silver is a new functional materials with small particle size, surface area, great activity, high catalytic activity, low melting point, good sintering performance, etc., while retaining the conductive metal silver, good antibacterial properties, electrical bright silver color cast, which is widely used as a catalyst material, anti-static materials, low-temperature superconducting materials, electronic pulp, bio-sensor materials and antibacterial, deodorant and absorb some of the UV protection materials. However, due to the presence of nano-powder surface area, surface atoms, more high surface energy, there is a lot of surface defects and dangling bonds between the particles easily agglomerate to form larger size aggregates, thus affecting the development and application of its products. At present, domestic and international research on nano silver dispersion is still relatively small, is not the system, thus further dispersion process and mechanism of nano silver dispersion has important practical significance. In this experiment, the polymer-surfactant polyvinyl-pyrrolidone (PVP), cationic surfactant cetyl trimethyl ammonium bromide (CTAB), and anionic surfactant sodium dodecyl sulfate ( SDS) and oleic acid as a dispersant for the silver to be dispersed, decentralized systems research time and surfactant concentration ultrasonic dispersion properties of nano silver in ethanol influence and make a preliminary study of its dispersion mechanism.

Fixed ultrasonic power for the next 560 W conditions, ultrasonic time, the type and concentration of surfactant has a major impact on the nano silver dispersion. With ultrasonic time and surfactant concentration increases, the powder dispersion after first increases and then decreases. PVP dispersion is better than CTAB, SDS and oleic acid. Nano silver in ethanol suitable dispersion process: ultrasonic time of 40 min, 1.5% PVP.