Microstructure Characterization of Magnesium Silicate Hydrate Phase

Author(s): Yuan Jia, Tingting Zhang, Baomin Wang, Luc J. Vandeperre and Chris R.Cheeseman
Paper category: Proceedings
Book title: 3rd International RILEM Conference on Microstructure Related Durability of Cementitious Composites
Editor(s): Changwen Miao, Wei Sun, Jiaping Liu, Huisu Chen, Guang Ye and Klaas van Breugel
Print-ISBN: 978-2-35158-188-9
e-ISBN: 978-2-35158-189-6
Publisher: RILEM Publications SARL
Publication year: 2016
Pages: 347-364
Total Pages : 14
Language : English

Abstract: Magnesium silicate hydrate (M-S-H) samples were synthesized in this study via the reaction of magnesium oxide (MgO) and silica fume (SF) in distilled water with different sodium hexametaphosphate (Na-HMP) contents, with one year of curing time at room temperature. A molecular scale and micro-structural characterization is essential for improving and controlling the physical and chemical properties of Mg cement-based materials: Here, we illustrate the reaction process of MgO-SiO2-H2O system and the molecular structure of M-S-H gel as-identified by transmission electron microscopy (TEM), solid state nuclear magnetic resonance (NMR), and Fourier transform infrared (FT-IR) spectroscopy. These techniques are well-suited to amorphous phase characterization and provide important information about the composition and structure at the nano- and micro-scale. M-S-H gel was observed to grow on the surface of particles and form a unique, core-sheel structure.
Compared to magnesium silicate hydrate minerals, the structure of M-S-H gel is more disordered. The structure of M-S-H gel was observed in the local layer or in network-like formation. Taken together, the results presented in this paper suggest that the structure and Mg/Si of M-S-H gel is related to pH value in the solution.

Online publication : 2016
Publication type : full_text
Public price (Euros) : 0.00