Liu Xinhui, Hu Chunfeng, Chu Longsheng
School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China.
Materials (Basel). 2020 Jul 19;13(14):3215. doi: 10.3390/ma13143215.
Geopolymer as an alternative to cement has gained increasing attention. The aim of this article is to study the influence of the silica fume content and activator type on the porous fly ash-based geopolymer with silica fume as foaming agent. Geopolymeric foams were fabricated using low-calcium fly ash, silica fume, and sodium-based alkaline activator as initial materials. The designed silica fume contents were 0, 15, 30, and 45 wt % and two kinds of activators of water glass and sodium hydroxide were used for comparison. Phase composition, microstructure, mechanical properties and sound insulation properties of as-prepared bulks were systematically investigated. It was found that, with increasing silica fume content, the density and compressive strength decreased simultaneously, whereas the porosity and sound insulation performance were effectively enhanced. At the silica fume content of 45% with sodium hydroxide as activator, the porosity was increased 3.02 times, and, at the silica fume content of 45% with water glass as activator, the mean sound insulation value of 43.74 dB was obtained.
地质聚合物作为水泥的替代品已受到越来越多的关注。本文旨在研究硅灰含量和活化剂类型对以硅灰为发泡剂的多孔粉煤灰基地质聚合物的影响。以低钙粉煤灰、硅灰和钠基碱性活化剂为原料制备地质聚合物泡沫。设计的硅灰含量为0、15、30和45 wt%，并使用水玻璃和氢氧化钠两种活化剂进行比较。系统研究了所制备块体的相组成、微观结构、力学性能和隔音性能。结果发现，随着硅灰含量的增加，密度和抗压强度同时降低，而孔隙率和隔音性能得到有效提高。以氢氧化钠为活化剂、硅灰含量为45%时，孔隙率提高了3.02倍；以水玻璃为活化剂、硅灰含量为45%时，平均隔音值为43.74 dB。
