THE EFFECT OF NANOADDITIVES ON THE HYDRATION OF GYPSUM BINDING AGENTS
Journal Title: Збірник наукових праць Українського державного університету залізничного транспорту - Year 2018, Vol 178, Issue 12
Abstract
The results of investigation of hydration processes of gypsum with carbon nanomodifiers are presented in the article. Gypsum modification by multilamellar carbon nanotube (CNT) results in the improvement of its compression strength. Experiments proved that at the nanotubes content of 0,18 %, strength improvement by up to 30 % is observed. Chemical functionalization of carbon nanotube surface facilitates the reduction of the sedimentation effect inherent to the nanoparticles, enables more uniform nanostructure dispersion throughout the modified material volume and provides the chemical interaction between nanotubes and the substance matrix. Quantum-chemical analysis methods confirm that the interaction of calcium sulfate dihydrate molecule with the dihydrate -like surface is the chemical process. The improvement of CNT-containing gypsum composite strength is due to the accelerated process of calcium sulfate dihydrate crystallization at the graphene surface. Therefore, it may be assumed that CNTs act as “crystallization nuclei” in the gypsum composite. The analysis of the microstructure of gypsum composition samples showed that without the modifying additive, loose structure of the gypsum samples is formed with a significant number of pores.It may be assumed that nanodispersed CNT additives act as “crystallization nuclei” on the surface of which calcium sulfate matrix structuring occurs with the improvement of the gypsum composition structural characteristics. This is due to the fact that during growth, crystals partly penetrate into each other and form three-dimensional network permeating and incorporating the entire gypsum stone into a body.
Authors and Affiliations
Viktor Derevianko, Hanna Hryshko, Wladimir Moroz
Keywords
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- EP ID EP396487
- DOI 10.18664/1994-7852. 178.2018.138994
- Views 73
- Downloads 0
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