Curcumin Nanocrystals as Photodynamical Sensor Monitoring Ultraviolet Accelerated Aging of HDPE

In this work, curcumin nanocrystals (CCN) was used as fluorescence probes for monitoring the accelerated aging of high density polyethylene (HDPE) used in insulation of high-voltage cables. CCN has been synthesized and incorporated into HDPE matrix using hydrothermal process (HydP) at 202.65 kPa and temperatures of 60 °C and 120 °C. The apparent activation energy (EA) for CCN incorporation into HDPE matrix was 54.4 kJ/mol. The resulting nanocomposite HDPE-CCN has been characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and fluorescence spectroscopy (FS). The crystallinity of HDPE and HDPE-CCN determined by DSC were 71.27% and 70.30% respectively, suggesting that the presence of CCN does not modify significantly the microstructure of HDPE. Accelerated aging of HDPE-CCN samples was carried out and the stress to break ( $\varepsilon _{\mathrm {b}}$ ), Young’s modulus (E) and fluorescence intensity (FI) were used as measurements of HDPE degradation. Mechanical properties ( $\varepsilon _{\mathrm {b}},\mathrm {E}$ ) and FI measurements do correlate with age-related material degradation on the HDPE samples examined.