Title:
Macro- and Micro-Characterization of Mortars Produced with Carbon Nanotubes
Author(s):
Valquíria S. Melo, Jose M. F. Calixto, Luiz O. Ladeira, and Adriano P. Silva
Publication:
Materials Journal
Volume:
108
Issue:
3
Appears on pages(s):
327-332
Keywords:
carbon nanotubes; mechanical properties; microstructure; mortar
DOI:
10.14359/51682498
Date:
5/1/2011
Abstract:
The incorporation of nanoscale particles into various materials has catalyzed certain mechanical properties. With large tensile strength, carbon nanotubes can improve the performance of Portland cement composites in this aspect. In this scenario, the goal of this paper is the evaluation of the performance of mortars produced with physically added multi-walled carbon nanotubes at ratios of 0.30, 0.50, and 0.75% of cement content. Two chemical admixtures—modified polycarboxylate and melamine-formaldehyde—were used. The investigated mechanical properties were the compressive and splitting tensile strengths and the secant modulus of elasticity (MOE). Scanning electron microscopy (SEM) and specific surface area (BET) were used for the microstructure analysis. Based on the results of specific surface area and pycnometry, a computer program was also employed to evaluate the microstructure. The analysis of the test results indicates the better performance of the mortars fabricated with 0.30% of carbon nanotubes and a modified polycarboxylate high-range water-reducing admixture.