Interactions, morphology and thermal stability of graphene-oxide reinforced polymer aerogels derived from star-like telechelic aldehyde-terminal benzoxazine resin

Abstract

Graphene oxide (GO)-reinforced nanocomposite aerogels of polybenzoxazine prepared via freeze-drying of GO suspensions in benzoxazine precursor solutions have been studied. The synthesis of GO is confirmed using Raman and Fourier transform infrared (FT-IR) spectroscopy. The benzoxazine monomer (SLTB(4HBA-t403)) has been synthesized using 4-hydroxybenzaldehyde as a phenolic component, paraformaldehyde, and tri-functional polyetheramine (Jeffamine T-403) as an amine source. The chemical structure of the benzoxazine monomer is confirmed by nuclear magnetic resonance (¹H-NMR) spectroscopy and FT-IR. The interactions of GO and SLTB(4HBA-t403) have been investigated using FT-IR. The morphological and thermal stability of nanocomposite aerogels are examined and compared with the neat polybenzoxazine aerogel. The structures of the aerogels and the effect of GO on the morphology of the aerogels are studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The effect of GO on the ring-opening polymerization of benzoxazine is also evaluated using differential scanning calorimetry (DSC) whereas the thermal stability of the nanocomposite aerogels is characterized by thermogravimetric analysis (TGA).