Static and dynamic mechanical thermoanalyses of cement paste with highly dispersed graphene oxide

Abstract

This study investigated the static mechanical properties of cement pastes with highly dispersed graphene oxide (GO), performed a dynamic mechanical thermoanalysis (DMTA), and studied the microstructure of cement pastes after exposure to high temperatures (105, 200, 300, 450, 600, and 750 °C). First, GO was uniformly dispersed in the cement paste with the aid of polycarboxylate-based superplasticizers. Generally, the incorporation of dispersed GO can enhance the residual compressive strengths of the cement pastes. For pastes with 0.04% GO (by weight) exposed to temperatures of 105, 200, 300, 450, 600, and 750 °C, the strengths are 14.84%, 4.83%, 13.35%, 15.71%, 11.91%, and 64.49% higher than that of pastes without GO, respectively. The DMTA results reveal that cement pastes with 0.04% GO have a high storage modulus and low loss factors in the temperature range of 25–350 °C, which improve their thermal resistance. Moreover, the addition of dispersed GO refines the pore structure and decreases the total porosity at high temperatures by suppressing the coarsening of the pore structure of cement pastes.