An amorphous, C-S-H-like phase with Ca/Si = 2 was synthesized from amorphous precipitated silica, calcium oxide, and water by mechanochemical treatment using a vibration mill at room temperature. The product was studied by XRD, 29Si MASNMR, TEM, analytical TEM, and TGA-DTA. After 14 h of treatment, the starting materials react to form an amorphous phase (C-S-H-like phase). The XRD pattern of C-S-H-like phase resembles the C-S-H formed hydrothermally or by cement hydration except it has no reflection at 0.182 nm. The 29Si NMR results revealed a silicate anion structure of C-S-H-like phase consisting mainly of a mixture of a monomer and a dimer. On heating, the C-S-H-like phase decomposed into β-dicalcium silicate below 1000°C.
|Number of pages||5|
|Journal||Journal of the American Ceramic Society|
|Publication status||Published - 1997 Feb 1|
ASJC Scopus subject areas
- Ceramics and Composites
- Materials Chemistry