13C,27Al and 29Si NMR investigation of the hydration kinetics of Portland-limestone cement pastes containing CH3-COO¯-R+(R=H or Na) additives

0555838 - ÚTAM 2023 RIV CH eng J - Journal Article
Mazur, A. - Tolstoy, P. M. - Sotiriadis, Konstantinos
13C,27Al and 29Si NMR investigation of the hydration kinetics of Portland-limestone cement pastes containing CH3-COO¯-R+(R=H or Na) additives.
Materials. Roč. 15, č. 6 (2022), č. článku 2004. E-ISSN 1996-1944
R&D Projects: GA ČR(CZ) GC21-35772J
Institutional support: RVO:68378297
Keywords : Portland-limestone cement * organic additives * hydration kinetics * NMR spectroscopy
OECD category: Materials engineering
Impact factor: 3.4, year: 2022
Method of publishing: Open access
https://doi.org/10.3390/ma15062004

The hydration kinetics of Portland-limestone cement pastes with organic additives in the form of acetic acid and sodium acetate were studied by using solid-state 13C, 27Al and 29Si NMR spectroscopy. The evolution of the relative content of various phases was monitored over the period of one month: amorphous and crystalline calcite (in 13C spectra), ettringite, aluminum in C-S-H gel, calcium aluminates and calcium hydroaluminates (in 27Al spectra), as well as alite, belite and silicon
in C-S-H gel (in 29Si spectra). The retarding effect of the additives on cement hydration at early age was demonstrated. We show that the kinetics of phase assemblage formation is influenced by the acetate ion adsorption on the surface of the anhydrous cement components and hydrated phases. The kinetics of formation of ettringite in the cement paste, depending on the addition of acetic and or sodium acetate, is discussed in the context of potential thaumasite sulfate attack.
Permanent Link: http://hdl.handle.net/11104/0330311