Combined Functionalization of Carbon Nanotubes (CNT) Fibers with H<sub>2</sub>SO<sub>4</sub>/HNO<sub>3</sub> and Ca(OH)<sub>2</sub> for Addition in Cementitious Matrix
Eduardo Batiston,
Paulo Ricardo de Matos,
Philippe Jean Paul Gleize,
Roman Fediuk,
Sergey Klyuev,
Nikolai Vatin,
Maria Karelina
Affiliations
Eduardo Batiston
Department of Civil Engineering, Community University of the Chapecó Regions, Chapeco 89809-900, Brazil
Paulo Ricardo de Matos
Department of Civil Engineering, Federal University of Santa Catarina, Florianópolis 88040-900, Brazil
Philippe Jean Paul Gleize
Department of Civil Engineering, Federal University of Santa Catarina, Florianópolis 88040-900, Brazil
Roman Fediuk
Polytechnic Institute, Far Eastern Federal University, 690922 Vladivostok, Russia
Sergey Klyuev
Department of Theoretical Mechanics and Strength of Materials, Belgorod State Technological University Named after V.G. Shukhov, 308012 Belgorod, Russia
Nikolai Vatin
Institute of Civil Engineering, Peter the Great St. Petersburg Polytechnic University, 195251 St. Petersburg, Russia
Maria Karelina
Department of Road-Building Materials, Moscow Automobile and Road Construction University, 125319 Moscow, Russia
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.
