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Silver is an important noble metal having excellent electrical conductivity and antibacterial properties. Nano Silver not only has the nature of the metallic silver, but also both the force, heat, light, electricity, and other aspects of the unique nature of nanomaterials, textile and other fields have a wide range of applications. Preparation of nano-silver is high cost, difficult to disperse, the particle size and morphology control is also more difficult. Coated nano silver powder surface, not only can save the amount of silver, but also easy to disperse, and the the silver deposition thickness, deposition morphology and sedimentary also easy to control. In this context, to a source of a wide and low price inorganic mineral raw materials - talc as a carrier, the use of chemical plating method, the surface coated with silver. Explore the silver plating process conditions and influencing factors, the talc surface modification as well as the surface active agent of the deposition process and deposition effects, final talc surface more complete, densely coated with a layer of silver nanoparticles. To the prepared silver plated talc used in nylon fabric coating finishing, to explore silver plated talc textile anti-bacterial, anti-ultraviolet and anti-static function. The main research contents and conclusions are as follows: (1) the pre-treatment process of the silver plating, talc roughened using HF, observed by scanning electron microscopy, the coarsening time of 20min. It was found that, due to increase SnCl2? 2H2O dosage, to extend the time of sensitization can deepen the color of the powder activated. But by SnCl2? 2H2O dosage excessive powder surface-coated uniformly decreased, so the selection of the treatment conditions: 20g / L by SnCl2? 2H2O 50mL / L HCl sensitized time of 15min; 2g / L silver nitrate solution activation, time 20min . (2) using a chemical silvering step three Reductant: formaldehyde, glucose, sodium potassium tartrate. It was found that different reducing agent, the coating morphology, formaldehyde as a reductant silver powder surface coated with the most complete, compact, and highest plating silver content; crystal structure of the coating are the face-centered cubic structure, coating firmly degree are better; the best formaldehyde formulations silver talc conductivity, silver plated chemical reaction rate is also the fastest. (3) formaldehyde as the reducing agent, using ammoniacal silver droplet penetration method, explore the the chemical silvering conditions: temperature, pH value, concentration, loading capacity, and the reaction time, to determine the best silvered conditions: temperature of 20 to 25 ℃, the ammoniacal silver solution pH = 11.7, silver nitrate concentration of 10g / L, the concentration of formaldehyde in 13mL / L, the amount of powder loaded 25g / L, chemical silvering reaction time of 60min. (4) After the amino silane coupling agent, an increase in the activation point of the talc surface coating coated more complete densification; silvered, different surface active agent is added in the coating effect on the talc surface and surface silver different effects of particle size, surface coating integrity: of SDBS (sodium dodecyl benzene sulfonate) gt; the SDS (twelve sodium lauryl sulfate) gt; PEG (polyethylene glycol) gt; PVP (polyvinylpyrrolidone ); silver particle size of the surface: PEG gt; SDS gt; of SDBS gt; PVP. Optimize the prepared silver plated talc (5), nylon fabric coating finish, coated fabrics study different silver content antibacterial, anti-ultraviolet and anti-static properties. The results showed that the silver content of 0.5%, the inhibitory rate gt; 90%; when the silver content is 1.0% to 2.0%, 30 lt; UPF LT; 50; silver content was 1.5%, the charge half-life of less than 10s.
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