Electric-arc resistant face shield or lens including ir-blocking inorganic nanoparticles

摘要

A transparent electric-arc resistant composition is produced by preparing crystalline tungsten bronze nanoparticles and homogenously dispersing the nanoparticles in a transparent plastic matrix. The crystalline tungsten bronze nanoparticles are prepared by homogeneously mixing an aqueous solution of soluble tungsten and cesium salts and then drying the solution. The dried solution is then heated in a reducing gas or inert gas atmosphere to form crystalline tungsten bronze nanoparticles. Thereafter, a dispersion agent is added and the nanoparticles are dispersed in a liquid solvent medium by wet milling to form a dispersion mixture. The dispersion mixture is then mixed with polymer pellets to form a polymer mixture, and the polymer mixture is then extruded to yield polymer pellets containing highly homogeneously dispersed inorganic nanoparticles. During or after dispersion, additional particles, dyes, heat stabilizers or UV absorbers, may be added. A lens or shield (10) is then molded from the polymer pellets.