Influence of super plasticizer and Ca(OH)2 on the stability of functionalized multi-walled carbon nanotubes dispersions for cement composites applications

This work studies the effect of superplasticizer and Ca(OH)2 on the stability of OH functionalized multi walled carbon nanotube (MWCNT)/water dispersions produced via sonication. Dispersion of the MWCNT/water/superplasticizer dispersions was quantified using UV-Vis spectroscopy, the damage induced on the MWCNT was identified using RAMAN spectroscopy and the effect of Ca(OH)2 stability of the dispersions was identified using Zeta potential and FTIR spectroscopy. It was found that Ca(OH)2 affects the stability of MWCNT dispersions due to its interaction with negative charges of the OH functional groups, which hinders the electrostatic repulsion between MWCNT and superplasticizer molecules, generating re-agglomeration of the MWCNT.