利用多孔微球发泡法制备泡沫玻璃及其烧成工艺研究

Glass Foams Prepared by Porous Microspheres Foaming Method and the Sintering Process Research

本工作以废玻璃粉为主要原材料制备多孔微球,利用多孔微球发泡法制备高气孔率的泡沫玻璃,研究了烧成温度、升温速率和保温时间对泡沫玻璃孔结构特征参数的影响,提出了利用多孔微球制备泡沫玻璃的最佳烧成工艺参数。结果表明:当玻璃粉球磨至D50为4μm左右时,可以制备高气孔率的泡沫玻璃。随着烧成温度的升高,泡沫玻璃的孔径增大,气孔率增加;适当提高升温速率可增加泡沫玻璃的气孔率,降低其体积吸水率;延长保温时间,泡沫玻璃的体积吸水率增加,析晶增多,主要晶相包括SiO_(2)(石英)、SiO_(2)(鳞石英)和Na_(2)Ca_(3)Si_(6)O_(16)(失透石)。利用多孔微球制备泡沫玻璃的最佳烧成温度为700~750℃,升温速率为3~5℃/min,保温时间为1~2 h。本实验制备的泡沫玻璃具有较高的抗压强度(0.8~2.9 MPa),可用作建筑保温材料。

Porous microspheres were prepared using waste glass powder as the main raw material,and glass foams with high porosity were prepared by the porous microspheres foaming method.The influence of sintering temperature,heating rate and holding time on the porous structure of glass foams was investigated.The optimum sintering parameters for the preparation of glass foams from porous microspheres were proposed.The results show that glass foams with high porosity can be prepared when the D50 of the glass powder is ground to be about 4μm.With the increasing of the sintering temperature,the cell size and the porosity increase.With the heating rate increasing in a reasonable range,the porosity increases,and the volumetric water absorption reduces.With the increasing of holding time,the water volumetric absorption and the crystal percentage increase.The main crystalline phases are quartz(SiO_(2)),tridymite(SiO_(2)) and devitrite(Na_(2)Ca_(3)Si_(6)O_(16)).The optimum sintering temperature,heating rate and holding time are 700—750℃,3—5℃/min and 1—2 h,respectively.The obtained glass foams with high compressive strength of 0.8—2.9 MPa can be used as building thermal insulation materials.