Chemical composition of nanomodified cement stone

¹ Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow, 129337, Russia
² Saint Petersburg State University of Architecture and Civil Engineering, Vtoraya Krasnoarmeiskaya street, 4, Saint Petersburg, Russia

^* Corresponding author: GrishinaAN@mgsu.ru

Abstract

Improving the properties of cement building materials is possible with the use of modifiers, including nanoscale ones. Such nanomodifiers include hydrosilicates of zinc and copper. The increase in the performance characteristics of nanomodified cement composites is due to changes in the chemical composition of the resulting cement stone, in particular, an increase in the content of hydrosilicate structures. The chemical composition of the cement stone was studied by FTIR-spectroscopy. Colloidal solutions of zinc and copper hydrosilicates with known characteristics were used for the nanomodification of cement stone. It is shown that when using copper hydrosilicates synthesized at high concentrations of iron hydroxide, the concentration of amorphous silica does not significantly affect the composition of cement stone. However, with a decrease in the concentration of iron hydroxide, with an increase in the concentration of amorphous silica, the content of hydrosilicate structures increases. The use of nanoscale zinc hydrosilicates is more efficient than copper hydrosilicates. Their use makes it possible to increase the content of structures containing silicon-oxygen tetrahedra, submicrocrystalline calcium hydrosilicates of a tobermorite-like structure in cement stone, and the formation of ettringite is also noted. Thus, it was found that the use of zinc hydrosilicates as nanomodifiers for cement stone allows increasing the content of hydrosilicate structures in hydration products.