Abstract
Since metakaolin obtained by dehydration of kaolin minerals at a temperature ranging from 500°C to 800°C shows high electric resistivity, and has stabilizing effect on vinyl chloride resin, it is used as fillers of vinyl chloride for making insulated electric wire.
In view of the fact that metakaolin of good quality has not yet been available in Japan, and so for most of its supply its importation from abroad has been relied upon, fundamental research attempts have been made to find a method of producing metakaolin of fine quality from Japanese kaolin minerals, the products of Zeeklite Chem. Mining Co.
As a result of experiments on dehydration of Japanese kaolin minerals using thermogravimetric analysis, differential thermal analysis and X-ray methods, it has been made evident that the reaction is of first order.
Some of the Japanese kaolin minerals dehydrated at a temperature of 800°C, surpass the imported metakaolin in whiteness. The particle size of the dehydrated product is somewhat coarser than that of the raw materials.
Several properties of the metakaolin-vinyl chloride compounds were measured by JIS K 6723 method, elucidating that Japanese metakaolin from the products of Zeeklite Chem. Mining Co. can be used as fillers of vinyl chloride for insulated electric wires.
