含水率对固态激发剂制备地质聚合物显微结构与性能的影响

Effect of Water Ratio on the Microstructure and Properties of Geopolymer Prepared by Solid State Activator

主要研究了固态激发剂制备地质聚合物样品中含水率对显微结构与抗折强度的影响,并对样品进行了XRD、SEM及EDS表征。结果表明:含水率为11%,混合料静置12 h时,抗折强度最大值为31.62 MPa。继续延长静置时间,样品抗折强度基本无变化;含水率过少或过多,均会引起样品结构中微裂纹的产生,使样品抗折强度下降。随静置时间的延长,养护后Na型针沸石相的特征衍射峰逐渐增强,形成一种硅铝摩尔比为1.13的单硅铝链状结构,其通过聚合生长方式朝不同方位穿插生长,最终形成针状聚集体形貌的沸石晶体,增大样品的抗折强度。

Effect of water ratio in raw mixtures on the microstructure and properties of fly ash based geopolymer was studied.XRD,SEM-EDS,TG-DTA and FTIR were employed to characterize the phases and microstructure of the samples with different water ratio.The results show that the bending strengths of the samples reach the maximum value 31.62 MPa when the water ratio of the mixture is 11%after being set aside for 12 h.While extending the setting time,the bending strengths of the samples have no significant changes.When the water ratio of the samples is too low or too high,microcracks could occur in the microstructure of the samples and thus decrease the bending strengths.A new needle-shaped zeolite phase is formed in the structure and the characteristic diffraction peak increases gradually with the increase of the setting time of the samples.A single silicon aluminum chain structure was formed with the mole ratio of silicon to aluminum of 1.13.The structure grows in different directions through the polymerization reaction and zeolite crystals with acicular aggregate morphology are formed which can increase the bending strength of the samples.