Incorporating Graphene Nanoplatelets and Carbon Nanotubes in Biobased Poly(ethylene 2,5-furandicarboxylate): Fillers’ Effect on the Matrix’s Structure and Lifetime

Abstract

Poly(ethylene 2,5-furandicarboxylate) (PEF) nanocomposites reinforced with Graphene nanoplatelets (GNPs) and Carbon nanotubes (CNTs) were in situ synthesized in this work. PEF is a biobased polyester with physical properties and is the sustainable counterpart of Polyethylene Terephthalate (PET). Its low crystallizability affects the processing of the material, limiting its use to packaging, films, and textile applications. The crystallization promotion and the reinforcement of PEF can lead to broadening its potential applications. Therefore, PEF nanocomposites reinforced with various loadings of GNPs, CNTs, and hybrids containing both fillers were prepared, and the effect of each filler on their structural characteristics was investigated by X-ray Diffraction (XRD), Fourier transform infrared spectroscopy—attenuated total reflectance (FTIR–ATR), and X-Ray Photoelectron Spectroscopy (XPS). The morphology and structural properties of a hybrid PEF nanocomposite were evaluated by Transmission Electron Microscopy (TEM). The thermo-oxidative degradation, as well as lifetime predictions of PEF nanocomposites, in an ambient atmosphere, were studied using Thermogravimetric Analysis (TGA). Results showed that the fillers’ incorporation in the PEF matrix induced changes in the lamellar thickness and increased crystallinity up to 27%. TEM analysis indicated the formation of large CNTs aggregates in the case of the hybrid PEF nanocomposite as a result of the ultrasonication process. Finally, the presence of CNTs caused the retardation of PEF’s carbonization process. This led to a slightly longer lifetime under isothermal conditions at higher temperatures, while at ambient temperature the PEF nanocomposites’ lifetime is shorter, compared to neat PEF.

Co-Incorporated N-Doped Micro–Meso Porous Carbon as an Electrocatalyst for Oxygen Reduction Reaction and Zn–Air Battery

“…The low surface percentage of Co in the samples Z 600 and ZL 600 (3:1) might be attributed to the surrounding carbon shells that may hinder the detection of cobalt (Table S1). Hence, it can be deduced that the etching with 1 M HCl has removed the Co content present on the surface of the carbon shells, while most of them are protected inside the carbon shells, as evident from the TEM images. , The C 1s spectrum exhibited peaks at 284.6, 285.2, 286, 286.8, and 289.1 eV, corresponding to CC sp 2 , C–C sp 3 , C–N, C–O, and CO, respectively. , The predominant peak of C–C sp 3 hybridization evidences the creation of defects in ZL 600 (3:1) (Figure b). The deconvoluted Co 2p spectrum drawn for ZL 600 (3:1) exhibited 2 peaks at 778.3 eV and 793.8, corresponding to 2p 3/2 and 2p 1/2 bands of Co nanoparticles (Figure c). , The deconvoluted N 1s spectrum of L 600 exhibited only one peak at 400.1 eV corresponding to pyrrolic nitrogen (Figure S3a).…”

“…62,63 The C 1s spectrum exhibited peaks at 284.6, 285.2, 286, 286.8, and 289.1 eV, corresponding to C�C sp 2 , C−C sp 3 , C−N, C−O, and C�O, respectively. 64,65 The predominant peak of C−C sp 3 hybridization evidences the creation of defects in ZL 600 (3:1) (Figure 5b). The deconvoluted Co 2p spectrum drawn for ZL 600 (3:1) exhibited 2 peaks at 778.3 eV and 793.8, corresponding to 2p 3/2 and 2p 1/2 bands of Co nanoparticles (Figure 5c).…”