Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8943109 | Cement and Concrete Composites | 2018 | 10 Pages |
Abstract
Efflorescence can be a critical issue for the application of alkali-activated fly ash-based geopolymer products, especially when the products are in a moist environment. In this study, a new method was explored to inhibit efflorescence of fly ash-based geopolymer via silane surface modifications. After the modification, the surface of the geopolymer was transformed from hydrophilic to hydrophobic, with a water contact angle of 144.1°, and the capillary absorption and diffusion of water were significantly suppressed; and as a consequence, the soluble alkali ion leaching was reduced. Analysis by Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and size-exclusion chromatography demonstrated that the selected silane is attached successfully onto the surface of the fly ash-based geopolymer via chemical bonding instead of via physical absorption. A possible reaction mechanism for the silane surface modification of the fly ash-based geopolymer is proposed.
Related Topics
Physical Sciences and Engineering
Engineering
Industrial and Manufacturing Engineering
Authors
Xiao Xue, Yun-Lin Liu, Jian-Guo Dai, Chi-Sun Poon, Wei-Dong Zhang, Peng Zhang,