Depolymerization of PET waste to potentially applicable aromatic amides: Their characterization and DFT study

Poly(ethylene terephthalate) waste has been depolymerized to a series of potentially applicable aromatic amides through aminolysis with different amines such as methylamine, ethylenediamine, ethanolamine, and butylamine at ambient conditions of temperature and pressure. The amides prepared were characterized by different techniques like Fourier transform infrared (FTIR), UV‐Visible spectroscopy, nuclear magnetic resonance (NMR), elemental analysis, mass spectrometry, powdered X‐ray diffraction (XRD), Raman spectroscopy, and thermal analysis. Further more, an attempt is being made to insight the physical parameters of the aromatic amides using ab initio DFT (Density Functional Theory) study. DFT calculations were performed at Becke's three parameter functional and Lee–Yang–Parr functional (B3LYP) level of calculation with 321‐G basis set. The atomic orbital energy (HOMO and LUMO) and energy gap is also represented. The vibrational frequencies optimized by DFT were in agreement with the experimental FTIR data. An efficient conversion of PET waste to amides was achieved without catalyst through environment friendly clean approach.