A comparative study of graphene oxide or chemically reduced graphene oxide filled poly(ethylene terephthalate)/poly(butylene terephthalate)/graphene nanocomposites

Graphene oxide (GO) or reduced graphene oxide (rGO) was used as nanofillers in the fabrication of poly(ethylene terephthalate)/poly(butylene terephthalate)/graphene (PET/PBT/G) nanocomposites. The nanocomposites were produced via melt blending and injection molding processes. The morphological, mechanical, thermomechanical, thermal, and electrical properties of the prepared nanocomposites were investigated. The SEM micrographs proved that GO-containing samples were brittle, while rGO-containing samples were more ductile. Also, there were agglomerations with the increase in the loading levels of nanofiller. The Young and storage moduli of PET/PBT/G nanocomposites were increased with increasing nanofiller loading levels and their increases in case of rGO was greater than those of GO. The glass transition temperatures of the PET/PBT blends were shifted to lower temperatures with the incorporation of nanofillers. While the tensile strength increased at lower amounts of nanofillers and decreased at higher amounts, elongation values showed a sharp decrease at all nanofiller loading levels. GO and rGO slowed the thermal degradation rate of the polymeric matrix. The char residue of the neat PET/PBT blend was 14.3% and increased with increasing GO and rGO loading levels. Electrical resistivity decreased significantly, and semiconductor type materials were obtained. Consequently, rGO was found to be a more suitable nanofiller to improve the properties of the prepared PET/PBT/G nanocomposites, compared to GO. [GRAPHICS] .