蒸压粉煤灰基地质聚合物发泡材料的微观结构及性能研究

Study on microstructure and properties of autoclaved fly ash-based geopolymer foam material

分析了以粉煤灰和矿粉为原料制备地质聚合物发泡材料,并利用饱和蒸汽工艺对其进行蒸压养护,以缩短制备过程养护周期的可行性,研究了不同激发剂模数和粉煤灰与矿粉比例条件下制备的地质聚合物材料的宏观性能及微观结构的差异。结果发现:当激发剂模数为0.6时,可得到力学性能最优的地质聚合物发泡材料,其抗压强度可达到2.03 MPa;当粉煤灰与矿粉质量比为7∶3时,可制得抗压强度为2.40 MPa的材料;粉煤灰基地质聚合物发泡材料在使用合适的激发剂模数时,可以产生晶粒较小、对材料孔结构影响较小的Na-X沸石,而矿粉的掺入可以抑制沸石的生成,保护材料孔结构。

The feasibility analysis was made for using fly ash and blast furnace slag as raw materials to make geopolymer foaming materials,and using saturated steam technology for their autoclaved curing so as to shorten the curing period of the preparation process.Four different activator moduli and four different fly ash and blast furnace slag ratios were selected to study the differences of macroscopic properties and microstructure of geopolymer materials prepared under above different conditions.The results showed that when the modulus of activator was 0.6,the geopolymer foam material with best mechanical properties could be obtained,with the compressive strength reaching 2.03 MPa;when the ratio of fly ash and blast furnace slag was 7∶3,the material with compressive strength of 2.40 MPa could be prepared.Fly ash-based geopolymer foam materials could produce Na-X zeolite with smaller crystal grains under the appropriate modulus of the activator,which had little effect on the pore structure of the material,and the blending of blast furnace slag could inhibit the formation of zeolite and protect material pore structure.