Other important indicators in silicone oil mainly include the following aspects:
1. Density: The density of silicone oil is usually between 0.93~0.975 g/mL (25/4°C). This indicator reflects the quality and volume of the silicone oil, which is important for certain applications that require precise control of the amount of silicone oil used.
2. Melting point: Silicone oil has a low melting point, generally between -50°C and -75°C. This means that the silicone fluid remains liquid at lower temperatures and has good low-temperature fluidity.
3. Boiling point: The boiling point of silicone oil varies with the pressure and degree of polymerization, but under certain conditions, its boiling point is higher. The high boiling point means that silicone oil is not volatile at high temperatures and has good thermal stability.
4. Flash point: The flash point of silicone oil is typically between 300°C and 315°C. The flash point is one of the important indicators to evaluate the safety of silicone oil, and a higher flash point means that silicone oil is not prone to safety accidents such as fire during use.
5. Viscosity: In addition to the previously mentioned CST (centistan) as a unit of kinematic viscosity, the viscosity of silicone oil can also be expressed in other units such as mPa·s. Viscosity is a direct reflection of the fluidity of silicone oil, and silicone oils with different viscosities are suitable for different application scenarios.
6. Solubility: Silicone oil is generally soluble in non-polar solvents, and difficult to dissolve in polar solvents. Solubility varies with the degree of polymerization, and low-molecular-weight silicone oils are more soluble than high-molecular-weight silicone oils.
7. Chemical stability: Silicone oil is relatively stable to fatty acids, molten sulfur, phenol, liquid ammonia, paraffin, etc., but under certain conditions (such as when interacting with solid salts such as ferric chloride and ammonium chloride), gelation and other changes may occur.
8. Electrical properties: Silicone oil has good electrical insulating properties, the dielectric constant decreases with the increase of temperature but changes little, the power factor is low, and the volume resistivity decreases with the increase of temperature.
9. Surface tension: Silicone oil has a low surface tension, which is an important reason for its excellent defoaming and antifoaming properties, isolation properties and lubricating properties.
10. Safety: Silicone oil is usually non-toxic, tasteless, odorless, and harmless to the human body, so it is widely used in medicine, food and cosmetics.
To sum up, the performance indicators of silicone oil cover many aspects such as physical properties, chemical stability and safety, which together determine the application performance of silicone oil in different fields.
