Microstructural changes of globules in calcium-silicate-hydrate gels with and without additives determined by small-angle neutron and X-ray scattering

作者：Chiang Wei Shan; Fratini Emiliano; Ridi Francesca; Lim Sung Hwan; Yeh Yi Qi; Baglioni Piero; Choi Sung Min; Jeng U Ser; Chen Sow Hsin^*

来源：Journal of Colloid and Interface Science, 2013, 398: 67-73.

DOI：10.1016/j.jcis.2013.01.065

• Calcium-silicate-hydrate
• Portland cement
• Polycarboxylic ether
• Small-angle scattering
• Colloid
• Fractal structure

The microstructure of calcium-silicate-hydrate (C-S-H) gel, a major hydrated phase of Ordinary Portland Cement, with and without polycarboxylic ether (PCE) additives is investigated by combined analyses of small-angle X-ray scattering (SAXS) and small-angle neutron scattering (SANS) data. The results show that these comb-shaped polymers tend to increase the size of the disk-like globules but have little influence on the thickness of the water and calcium silicate layers within the globules. As a result, the fractal packing of the globules becomes more open in the range of a few hundred nanometers, in the sense that the mass fractal dimension diminishes, since the PCE adsorption on the globules increases the repulsive force between and polydispersity of the C-S-H units. Moreover, scanning electron microscope (SEM) study of the synthesized C-S-H gels in the micrometer range shows that the PCEs depress the formation of fibrils while enhancing the foil-like morphology.

• 出版日期2013-5-15