Improvement of Cementitious Binders by Multi-Walled Carbon Nanotubes

To improve the mechanical properties of building materials carbon nanotubes (CNTs) were incorporated into normal concretes, high and ultra-high performance concretes as well as into model systems. Besides their outstanding mechanical properties CNTs are a very promising reinforcement material for composites because of their high aspect ratio, high resistance to corrosion and low specific weight. Multi-walled carbon nanotubes (MWCNTs) showed an influence on the hydration of binders and their macro- and microscopic mechanical properties. The effects of the nanostructures on the hydration, the composition and the micro- and nanostructure of the composite were investigated by the use of the in situ x-ray powder diffraction, isothermal calorimetric measurements, an ultrasonic method, imaging methods and the grid nanoindentation technique. The results show that the MWCNTs influence the hydration, the microstructure and are leading to improved mechanical properties of the composite. This presentation shows thermal analysis and porosimetry data of samples prepared with MWCNTs.