The influence of CNT-doped carbon aerogels on microstructural, rheological and mechanical properties of epoxy nanocomposites

Abstract In this study, CNT-doped carbon aerogel (CNT-CA) and carbon aerogel (CA) were used in different weight ratios (0.1, 0.3, and 0.5 wt%) to reinforce epoxy (Ep) nanocomposites. The relationship between the aerogels’ structure deformation such as the average diameter, the total volume of pores, specific surface area, and interfacial (particle/matrix) interaction, distribution, rheological, mechanical, and thermal properties were investigated systematically. Also, the nanocomposites were investigated by ATR-FTIR, XRD, and Raman spectroscopy. In general, the fabricated nanocomposites showed enhanced properties compared to the neat epoxy which is attributed to the penetration of polymer chains into the porous three-dimensional structure of the distributed aerogels. This phenomenon resulted in a high filler/matrix interaction, resulted in a better load transfer. Ep/CNT-CA showed better properties than Ep/CA which is due to ultrahigh specific surface area in CNT-CA. The rheological analysis showed a significant change in behavior from a liquid-like state to a pseudo-solid state in Ep/CA0.3 and Ep/CNT-CA0.1. Mechanical and thermal investigations of nanocomposites showed 8–17% increment in young modulus, 39–52% in tensile strength, 47–69% in elongation at break, 28–53% in E′ at 40 °C, 2–6% in Tanδ, and 7–11 °C in Tmax (compared to the neat epoxy matrix).