Aramid–multiwalled carbon nanotube nanocomposites: effect of compatibilization through oligomer wrapping of the nanotubes

Abstract

AbstractAramid–multiwalled carbon nanotube (MWCNT) nanocomposites with different CNT loadings were prepared by the solution‐blending technique. Aramid oligomeric chains having reactive amine end‐groups were covalently grafted and wrapped over the surface of acid‐functionalized MWCNTs. The presence of functional groups and surface modification of MWCNTs were studied using Raman, Fourier transform infrared and X‐ray photoelectron spectroscopic and transmission/scanning electron microscopic techniques. Addition of these MWCNTs resulted in a homogeneous dispersion throughout the aramid matrix. Dynamic mechanical thermal analysis showed an increase in the storage modulus and the glass transition temperature involved with α‐relaxations on CNT loading. The coefficient of thermal expansion (CTE) of aramid was reduced on loading with such CNTs. Strong interfacial interactions of the matrix with the surface‐modified CNTs reduced the stress‐transfer problem in the composite material and resulted in higher modulus of 4.26 GPa and a glass transition temperature of 338.5 °C, whereas the CTE was reduced to 101.8 ppm °C−1 on addition of only 2.5 wt% CNTs in the aramid matrix. © 2016 Society of Chemical Industry