Microwave assisted functionalization of carboxylated‐multiwalled carbon nanotubes with 5‐aminoisophthalic acid and its application for the preparation of chiral poly(ester‐imide)/ CNT nanocomposites

This article presents the results of investigation into surface modification of carboxylated‐multiwalled carbon nanotubes (MWCNT)s by 5‐aminoisophthalic acid under microwave irradiation as a fast, safe, and simple method. The different contents of functionalized MWCNTs (5, 10, 15 wt%) were effectively dispersed in an aromatic polymer through ultrasonic irradiation to prepare MWCNT reinforced polymer nanocomposites (NC)s. The chiral poly(ester‐imide) (PEI) was prepared by a direct polycondensation of chiral diacid with 4,4′‐thiobis(2‐tert‐butyl‐5‐methylphenol). The effect of the presence of MWCNTs on morphological and thermal properties of the NCs was investigated by X‐ray diffraction, FT‐IR spectroscopy, thermogravimetric analysis (TGA), transmission electron microscopy, and field emission scanning electron microscopy. According to TGA data, the PEI/MWCNT NCs showed a much better thermal stability than pristine polymer. The microstructure study of the NCs indicated the compatibility of functionalized MWCNTs with PEI and uniform distribution of them in the polymer matrices. POLYM. COMPOS., 37:835–843, 2016. © 2014 Society of Plastics Engineers