RESEARCH OF THE PREPARATION OF ULTRAFINE CALCIUM SULPHATE WHISKERS USING GYPSUM

Hydrothermal method was applied in the preparation of calcium sulfate whiskers in airtight reacor using CaSO₄·2H₂O as primary materials.The optimum conditions of preparation are as follows:temperature 120℃,pH value 9.8～10.1,concentration 5%,material size 18.1μm,which were determined by the analysis of the diameter of CaSO₄ whiskers through SEM.Under these conditions a product of ultrafine CaSO₄ whiskers with diameter of 0.19μm and aspect ration of 98 is obtained.