On the Application of Carbon Nanomaterials as Modifying Additives in Cement-Based Composites

This article presents the results of a study on the effect of carbon nanosized additives on the structure and properties of cement-based materials. The use of a carbon black dispersion as an alternative to an expensive dispersion of carbon nanotubes is proposed. Based on the experimental data, it is proven that the introduction of carbon black particles into the composition of the cement matrix in an amount of 0.2% by the weight of cement leads to an increase in strength of the cement stone, in both compression and bending, by 21% and 8%, respectively. This increase is compatible with the results obtained when cement matrix was modified with a dispersion of carbon nanotubes.IR spectral and thermal analysis of the modified cement matrix, as well as the study of its microstructure, confirm the formation of a dense net of cement hydration products, including low-basic calcium silicate hydrates and secondary nanosized globular thaumasite formations that contribute to the compaction of the material structure and the following increase in strength.