The geopolymers were prepared by calcining kaolinite. The structure transformation for calcined kaolinite was studied by means of differential thermal analysis-thermal gravity, X-ray diffraction and infrared. The results show that heat treatment directly affects the structure transformation of kaolinite and activity of calcination kaolinite. The structure transformation for calcined kaolinite is undergone some stages including kaolinite dehydroxylation (about 541 ℃), metakaolinite formation (541-850 ℃) and Al2O3 segregation (>950 ℃. The new phase formed at 950 ℃ is γ-Al2O3. The activity of calcined kaolinite is estimated by testing the bending strength of geopolymers which are made of calcined kaolinite, the heat treatment of proper calcined kaolinite activity is calined at 850 ℃ for 3 h. The calcined kaolinite has a high activity because of long-range disorder of metakaolinite structure characteristic. The activity of calcined kaolinite and bending strength of geopolymers decrease because of γ-Al2O3 forming.%采用煅烧高岭石的方法制备矿物聚合材料,采用DTA-TG、XRD和IR分析等手段研究高岭石经过热处理后的结构转变过程.结果表明:热处理直接影响到高岭石结构转变及煅烧高岭石的活性.煅烧后,高岭石的结构转变经历了脱羟基(约541℃)、偏高岭石化(541～850℃)和Al2O3分凝(＞950℃)3个过程,煅烧温度达到950℃后,生成新相γ-Al2O3.通过对煅烧高岭石所制备的矿物聚合材料抗折强度的评价确定了煅烧高岭石活性较适宜的热处理制度:煅烧温度为850℃,煅烧时间3h.煅烧高岭石的长程无序特征是煅烧高岭石具有较高活性的原因,γ-Al2O3的生成是导致煅烧高岭石活性下降和矿物聚合材料抗折强度降低的主要原因.
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