In this paper, different types of polyurethane potting materials were developed successfully by taking propylene epoxide-tetrahydrofuran polyether or polytetrahydrofurane glycol as polymer polyols, toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), and 3,3′-dimethyl-4,4′-biphenyl diisocyanate (TODI) as curing agents, and adding an appropriate amount of silica aerogel. The mechanical property, proccessability, low temperature resisitance, high temperature resistance, resistance to high and low temperature shock, and insulting property of the polyurethane potting materials were analyzed systematically. The results show that the polyurethane potting material formulated with propylene oxide-tetrahydrofuran copolymer and TODI as primary components, supplemented with silica aerogel with the mass fraction of 0.5%, exhibits outstanding processability, mechanical strength, and electrical insulation. It also demonstrates exceptional tolerance to extreme temperature fluctuations. This material achieves a glass transition temperature as low as -69.3°C and maintains a compression cold resistance coefficient of 0.54 at -60°C. Its 5% weight loss temperature reaches 302.3°C. After enduring 20 cycles of thermal shock between -65°C and 125°C, the material retains 93.5% of its tensile strength with a dimensional change rate of merely -0.6%, while preserving excellent insulation properties: volume resistivity of 4.2×10¹² Ω·cm and dielectric strength of 25 kV/mm.