Concentration Measurement of Antioxidant 1010 in Cross-Linked Polyethylene by Terahertz Time-Domain Spectroscopy

Antioxidants play a key role in the long-term safe operation of cross-linked polyethylene (XLPE) insulated cables, so their concentration is particularly important in the factory testing step process. In this article, a method for the concentration measurement of antioxidant 1010 (CAS:6683-19-8) in XLPE was proposed by using terahertz time-domain spectroscopy (THz-TDS) technology. By utilizing a transmission THz-TDS system, we obtained the THz time-domain waveforms, spectra, and refractive indices of XLPE samples containing different concentrations of antioxidant 1010, found the relationship between the antioxidant concentrations and the peak-to-peak values of the THz time-domain waveforms, the peaks of the spectra, and the average refractive indices, and obtained three fitting curves as calibration curves to accurately calculate the concentration of antioxidant 1010 in the XLPE samples. This article illustrates the feasibility of utilizing the THz-TDS technique to quantitatively detect antioxidant 1010 in XLPE and its superiority has been demonstrated through comparative experiments with Fourier transform infrared spectroscopy.