The Effect of CNT ‐modified matrix of cyanate ester CFRP s on the hydrothermal behavior of the material. Evaluation of the water uptake using electrical resistance measurements

In this work, reference and nanomodified unidirectional cyanate matrix, carbon fiber‐reinforced polymers (CFRPs), were exposed to distilled water at 80°C. Water uptake was investigated as a function of the carbon nanotube CNT wt% content up to saturation level. In parallel the variation of glass transition temperature ( T _g ) was also monitored using dynamic mechanical analysis tests. The distilled water absorption process was modeled following the Fick's law, and the experimental results were found to be in very good agreement with the theoretical predictions up to saturation. Finally, during the tests and, at defined time intervals the variation of the electrical conductivity of the materials under investigation was studied and a correlation between the water absorption and the variation of the electrical conductivity was established. It was shown that the presence of CNTs into the cyanate matrix affects the water absorption mechanism, since an important amount of additional interfaces has been introduced. POLYM. COMPOS. 37:1072–1077, 2016. © 2014 Society of Plastics Engineers