One-pot synthesis of glucose functionalized multi-walled carbon nanotubes: Dispersion in hydroxylated poly(amide-imide) composites and their thermo-mechanical properties

Multi-wall carbon nanotubes (MWCNTs) were functionalized with glucose using a covalent, non-specific functionalization approach. Fourier-transformed infrared spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM) confirmed that glucose structures were covalently attached to CNTs. Hydroxylated poly(amide-imide) (PAI)-based composites were developed by dispersing of glucose-functionalized MWCNTs (MWCNTs-GI) as reinforcement in different concentrations varying from 5 to 15 wt.%. Nanocomposites have slightly higher degree of crystallinity than neat PAI and their thermooxidative stability was significantly affected by the addition of MWCNTs-GI. According to mechanical tensile tests, the tensile strength and the Young's modulus of the MWCNT-GI/PAI composites were increased with increasing MWCNTs-GI content. The tensile strength remarkably increased from 81 to 129 MPa, which was about 59% higher than that of the neat PAI, with the addition of MWCNT-GI contents within 15 wt.% and the elongation at break decreased about 0.2% at a 5 wt.% loading of MWCNT-GI in comparison with the pure PAI film. (C) 2013 Elsevier Ltd. All rights reserved.