Abstract
Recycled polyethylene terephthalate (RPET) was doped with Neodymium Oxide (Nd(2)O(3): 0, 1, 2, 4, and 8 wt.%) to investigate its structural, optical, dielectric, and mechanical properties. X-ray diffraction (XRD) analysis revealed that pure RPET exhibited an amorphous structure, while the incorporation ofNd(2)O(3) induced the formation of crystalline phases, with crystallinity increasing as the Nd(2)O(3) concentration increased. Fourier-transform infrared (FTIR) spectroscopy identified chemical interactions between RPET and Nd(2)O(3), evidenced by a new band around 535 cm(-1). Optical analysis using diffuse reflectance UV-Vis spectroscopy showed a reduction in the band gap from 3.75 eV for pure RPET to 2.25 eV in 8wt.% doped samples, indicating enhanced optical properties. Dielectric studies revealed that Nd(2)O(3) doping significantly decreased the dielectric constant of RPET, contributing to the thermal stability of the dielectric constant. Furthermore, the dielectric loss and conductivity improved, with enhanced stability observed across varying temperatures. Dynamic mechanical analysis (DMA) revealed that adding 8 wt.% Nd(2)O(3) reduced the storage modulus of RPET from 1.62 GPa to approximately 0.26 GPa at 35 °C, attributed to structural softening. These improvements suggest that Nd(2)O(2)-doped RPET is suitable for applications requiring conductive REPT, low storage modulus, thermal stability, and enhanced energy dissipation capabilities.