Mechanical and morphological properties of highly dispersed carbon nanotubes reinforced cement based materials

作者：Wang Baomin^*; Han Yu; Pan Baofeng; Zhang Tingting

来源：Journal of Wuhan University of Technology-Materials Science Edition, 2013, 28(1): 82-87.

DOI：10.1007/s11595-013-0645-1

• carbon nanotubes
• Portland cement
• dispersibility
• reinforcement
• morphological properties

Stable homogeneous suspensions of multi-walled carbon nanotubes (MWCNTs) were prepared using gum arabic (GA) as dispersant and were incorporated to Portland cement paste. The dispersion was examined by ultraviolet visible spectroscopy (UV-vis), and the concentration measurement shows that the optimum concentration of GA is 0.45 g center dot L-1. The dispersibility of the surface-modified MWCNTs in aqueous solution and cement matrix were investigated by transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS), and the mechanical properties of the composites were investigated. The results show that the addition of the treated nanotubes can improve both the flexural strength and the compressive strength of the Portland cement composite significantly. The flexural strength of the composite increases up to 43.38% with the MWCNT concentration of 0.08% (by weight of cement). The porosity and pore size distribution of the composites were measured by mercury intrusion porosimetry (MIP), and the results indicate that the cement paste doped with MWCNTs obtained lower porosity and concentrated pore size distribution. The morphological structure was analyzed by field emission scanning electron microscopy (FESEM) and EDS. It is shown that MWCNTs act as bridges and networks across cracks and voids, which transfer the load in case of tension, and the interface bond strength between the nanotubes and matrix is very strong.

• 出版日期2013-2
• 单位大连理工大学