Effects on Thermal Aging and UV-A Aging on Dielectric Performance of High Temperature Vulcanized Silicone Rubber

• Published in: 2021 6th International Conference on Power and Renewable Energy (ICPRE) pp. 144 - 147
• Main Authors: Wang, Mengqi, Yu, JiaChen, Li, Jiacai, Liu, Hao, Shen, Wei, Li, Shengtao
• Format: Conference Proceeding
• Language: English
• Published: IEEE 17.09.2021
• Subjects: Cross linking; Dielectric parameters; Frequency-domain analysis; Heating systems; HTV-SIR; Morphology; Nanoparticles; Polarization; Renewable energy sources; Silicon compounds; Thermal aging; Thermal property; THz-TDS; UV-A aging
• ISSN: 2768-0525
• DOI: 10.1109/ICPRE52634.2021.9635514

High temperature vulcanized silicone rubber (HTV-SIR) was aged at 200 °C and under UV-A radiation. The dielectric parameters increased more after thermal aging than that after UV-A aging in 0.4-1.8 THz. Results of Fourier transform infrared spectroscopy showed that the side chains of HTV-SIR cracked after thermal aging. The content of Si-O increased slightly, indicating the cross-linking degree increased. After UV-A aging, the side chains and main chains of HTV-SIR were broken, and the cross-linking degree decreased. Besides, the cross-section morphology showed that the number of nanoparticles in HTV-SIR increased after UV-A aging. Moreover, DSC results showed that the "thawing" endothermic of HTV-SIR increased from −45 to −40°C after thermal aging, but that of UV-A aging samples decreased. After thermal aging, the dielectric parameters in terahertz frequency domain increased with the increase of molecular gap, the increase of density and electron polarization due to the invasion of oxygen, and the fracture of molecular bond. After UV-A aging, the molecular chain became shorter, the molecular gap became smaller and SiO 2 precipitated, which made the increase of polarization less than that of thermal aging, so the improvement of dielectric parameters was less than that of thermal aging.