Abstract
Nanocomposites prepared by mixing nanoparticles into polymer are expected to have such novel functions as flame-retardant, conductive and biodegradable capabilities. Most of the current fabrication methods of nanocomposites, however, are rather complicated and require high energy. The purpose of this study is to establish a simple fabrication method of nanocomposite based on hetero-coagulation in the liquid phase where a pair of polymer latexes are mixed with inorganic particles. We focused on flame retardancy as an index of the functional novelty, and used silica particles and acrylonitrile-styrene (AS) copolymer latex. The local structure of the aggregated materials made of these two entities through hetero-coagulation was observed via scanning electron microscopy, and found to be in a well-mixed state. The thermal decomposition temperature of the nanocomposite exceeded that of pure AS resin as measured via thermogravimetric analysis under nitrogen atmosphere. From the results of cone-calorimeter measurement and horizontal burning test, it was also found that the flame retardant capability of the present nanocomposite enhanced with an increase in the amount of silica particles or a decrease in the size of silica particles.
