TY - JOUR
T1 - Effects of carbon nanotubes on the early-age hydration kinetics of Portland cement using isothermal calorimetry
AU - MacLeod, Alastair J.N.
AU - Collins, Frank G.
AU - Duan, Wenhui
N1 - Funding Information:
The authors wish to acknowledge the financial assistance of the Australian Research Council Discovery Grant (DP110101095), and the use of the facilities at the Monash Centre for Electron Microscopy, using equipment funded by the Australian Research Council's Centre of Excellence for Design in Light Metals. The authors also acknowledge the assistance of Eden Innovations for the provision of carbon nanotubes, and Sika Australia for the supply of concrete admixtures for this research.
Publisher Copyright:
© 2021 Elsevier Ltd
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2021/5
Y1 - 2021/5
N2 - The addition of carbon nanotubes (CNTs) to cementitious nanocomposites have demonstrated significant mechanical performance enhancements, however, there has been only limited research of the effects of CNTs upon hydration kinetics. Isothermal calorimetry was used to study in detail (i) CNT dispersion with and without a polycarboxylate-based superplasticiser, (ii) CNT dose at 0.05–0.25 wt% of cement, and (iii) CNT dispersion quality upon cement hydration. Results show a 45-min acceleration and 17% increase in principal hydration peak at a CNT dose of 0.1 wt% without superplasticiser, indicating enhanced nucleation with CNTs. Varying CNT dose, delaying effects of the superplasticiser dominated, although there was an increase in hydration peak of 17% with 0.25 wt% CNTs. Finally, it was found that CNT content, not ‘good’ or ‘poor’ dispersion quality, had a greater effect upon the overall nanocomposite hydration and microstructural development, facilitating further optimisation of CNT dispersion and microstructural development for CNT-cement nanocomposites.
AB - The addition of carbon nanotubes (CNTs) to cementitious nanocomposites have demonstrated significant mechanical performance enhancements, however, there has been only limited research of the effects of CNTs upon hydration kinetics. Isothermal calorimetry was used to study in detail (i) CNT dispersion with and without a polycarboxylate-based superplasticiser, (ii) CNT dose at 0.05–0.25 wt% of cement, and (iii) CNT dispersion quality upon cement hydration. Results show a 45-min acceleration and 17% increase in principal hydration peak at a CNT dose of 0.1 wt% without superplasticiser, indicating enhanced nucleation with CNTs. Varying CNT dose, delaying effects of the superplasticiser dominated, although there was an increase in hydration peak of 17% with 0.25 wt% CNTs. Finally, it was found that CNT content, not ‘good’ or ‘poor’ dispersion quality, had a greater effect upon the overall nanocomposite hydration and microstructural development, facilitating further optimisation of CNT dispersion and microstructural development for CNT-cement nanocomposites.
KW - Carbon nanotubes
KW - Hydration kinetics
KW - Isothermal calorimetry
KW - Nucleation
KW - Superplasticiser
UR - http://www.scopus.com/inward/record.url?scp=85101803986&partnerID=8YFLogxK
U2 - 10.1016/j.cemconcomp.2021.103994
DO - 10.1016/j.cemconcomp.2021.103994
M3 - Article
AN - SCOPUS:85101803986
SN - 0958-9465
VL - 119
JO - Cement and Concrete Composites
JF - Cement and Concrete Composites
M1 - 103994
ER -