Combined Functionalization of Carbon Nanotubes (CNT) Fibers with H2SO4/HNO3 and Ca(OH)2 for Addition in Cementitious Matrix

Published on Mar 1, 2021in Fibers
· DOI :10.3390/FIB9030014
Eduardo Roberto Batiston1
Estimated H-index: 1
Paulo Ricardo de Matos10
Estimated H-index: 10
+ 4 AuthorsMaria Karelina3
Estimated H-index: 3
Acid treatment is commonly used to improve the dispersion of carbon nanotubes (CNT) in a cementitious matrix, but it causes undesired delay on cement hydration kinetics. This work reports a combined CNT functionalization method with H2SO4/HNO3 and Ca(OH)2 for addition in a cementitious matrix. Results showed that the Ca(OH)2 exposure neutralized the active sites generated by acid exposure, compensating the delay in hydration. As a result, CNT exposed to H2SO4/HNO3 for 9 h and further Ca(OH)2 treatment led to equivalent hydration kinetics than un-treated CNT did with improved stability.
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