偏高岭土基地质聚合物的制备

Preparation of Metakaolin-based Geopolymer

以偏高岭土为主要固体原料，掺加少量粉煤灰和矿渣，以硅酸钠水玻璃为碱激发剂，制备了偏高岭土基地质聚合物。研究了粉煤灰含量、水玻璃模数、养护方式和矿渣掺量对样品抗压强度的影响。结果表明，在粉煤灰含量为35％、硅酸钠水玻璃模数为1．2、矿渣含量为10％时样品具有较高的抗压强度，养护温度为常温时，28天强度为72MPa，80℃时可达80MPa；通过XRD和MAS-NMR微观分析表明制备的地质聚合物具有类沸石结构，其微观结构形态为无定形态；Si-O-Al-的键接方式主要为SiQ4（4A1）、SiQ（2A1）和Sid（4Si）。

Abstract In this paper, the influences of the factors, including the mass of fly ash, the modulus of sodium silicate, the method of and the amount of slag on the compress strength of metakaolin-based geopolymer are synthesized main- ly from metakaolin,a spot of fly ash and slag and the alkli activator： sodium silicate solution. It is concluded that while the mass fraction of fly ash is 35%o, the modules of sodium silicate is 1.2 and the mass fraction of slag is 10%, the sample will gain higher compress strength. Metakaolin-based geopolymer cured at 80℃ gains higher compress strength than that of cured at 25℃. XRD and MAS-NMR are used to analyze the microstrueture of products, which gains a three dimensional framework, like the zeolite crystals with anamorphous structure. SiQ^4 （4Al）, SiQ^4 （2Al） and SiQ^4 （4Si） are the main types of -Si-O-Al-bonds.