2. Theoretical analysis
The experimental results of the weather resistance of simethicone oil are analyzed from two aspects, one is the functional group structure of the substance, and the other is the bond energy of the chemical bond possessed by the substance.
There are no active groups in silicone oil, so the chemical properties are very stable, and there is no chromophore (groups that produce absorption bands in the ultraviolet and visible light regions are chromophores, simple chromophores are composed of double or triple bond systems) and auxiliary Chromophore (itself has no chromophore function, but when connected with chromophore, n-π conjugation will occur to enhance the chromophore’s chromogenic ability, so that the absorption wavelength of chromophore moves to the long-wave direction and the absorption intensity increase, such as -OH, -OR, -NH, -NHR, -X, etc.), so there is no absorption in the ultraviolet-visible region. After the experiment, there was no chromophore and auxochrome in the silicone oil, so the transmittance of the silicone oil decreased very little after the experiment, and this part of the decrease was probably caused by the slight dissolution of the battery surface substances, not the problem of the silicone oil itself.
Generally, the higher the bond energy, the higher the chemical stability. Simethicone oil has excellent oxidation stability and weathering resistance. From the structural analysis, it is as follows: because the electronegativity of Si and 0 (Si: 1.74, O: 3.50) is very different, the Si-O bond energy Larger, Si-O is close to the ionic bond and SiO2, and the composition of the rock structure is similar. This is one of the important reasons why polyorganosiloxane as a Si-O-Si chain has good thermal stability, and there is no double bond in the silicone oil molecule , so it is not easy to be oxidized in case of oxygen and thermally stable. In the experiment, silicone oil showed good tolerance.


3. Conclusion
Simethicone oil is a cooling medium suitable for liquid immersion cooling of concentrating systems. Through the high temperature 85 ℃, 150 ℃ experimental ultraviolet experiment and temperature ultraviolet coupling experiment, it is found that: silicone oil has excellent weather resistance, and the transmittance after the experiment decreases very little and concentrates in the ultraviolet region; the property is stable and it is extremely difficult to undergo chemical reactions; The electrical performance of the silicon battery immersed in silicone oil did not decline significantly, but a small amount of substances were precipitated on the surface of the battery.