01. Low surface tension
Polysiloxane has low cohesive energy density, low intermolecular force, and high compliant state, which leads to low surface tension. Because the solubility parameter of siloxane is far lower than that of other compounds and materials, and the surface tension is low, so the silicone resin has obvious incompatibility, that is, it is not easy to mix with other substances, so as to show excellent anti-viscosity.
02. Thermal stability
The heat resistance of silicone resin is far better than the general organic resin, it can be used in 200~250℃ for a long time without decomposition or discoloration, a short time can be resistant to 300℃, if with heat-resistant color fillers, silicone coating can withstand higher temperature. Organic silicon can not only high temperature resistance, and resistant to low temperature, and its chemical properties and physical properties with temperature change is very small, that is easily with organic silicon molecules around the curve of spiral structure, when the temperature rises, on the one hand, increases the average distance between molecules, on the other hand spiral extension to reduce the distance between the molecules, stretching and contraction of the spiral can alleviate the effects of temperature, Therefore, it has excellent temperature resistance.
3. The weather
Weatherability is one of the main characteristics of silicone resin, so it is widely used as film forming polymer of high weatherability coatings. There are two reasons for the good weatherability of silicone resin. One is that the Si-O bond in silicone resin is very stable, and it is difficult to produce free radical reaction caused by ultraviolet light, and it is not easy to produce oxidation reaction. The other is that silicone is insensitive to sunlight.
It is known that the wavelength of sunlight spectrum distribution on the earth surface is more than 300nm, and most organic resins are very sensitive to the light in this wavelength region, which is the root cause of poor weatherability of organic resins. And methyl siloxane almost does not absorb ultraviolet light, so the influence of sunlight on silicone resin is small, which is the main reason for the excellent weatherability of silicone coating.