1,1,5,5-Tetraphenyl-1,3,3,5-tetramethyltrisiloxane
Chemical Structure
Introduction
SiSiB® PF8704 Silicone Diffusion Pump Fluid is a single component fluid designed for high vacuum applications in the range of 10-6 to 10-8 torr (untrapped) and 10-10 to 10-11 torr (trapped).
Its low vapor pressure and thermal stability make it popular in processes such as vacuum coating, metallurgical work, and various other applications.
SiSiB® PF8704 is equal to DowCorning’s DC-704, Shin-Etsu’s HIVACF-4.
Typical Physical Properties
| Product: | SiSiB®PF8704 |
| CAS No.: | 3982-82-9 |
| EINECS No.: | 223-620-5 |
| Empirical Formula: | C28H32O2Si3 |
| Molecular Weight: | 484.82 |
| Color and Appearance: | Colorless to straw-colored fluid |
| Ultimate Vacuum, torr | 10-7 to 10-8 untrapped 10-10 to 10-11 trapped |
| Extrapolated Vapor Pressure, torr, 25°C | 2 x 10-8 |
| Specific Gravity at 25°C | 1.07 |
| Refractive Index at 25°C | 1.550~1.560 |
| Viscosity at 25°C | 36~44 cSt |
| Flash Point, open cup | 221°C |
| Boiling Point, 0.5 torr | 215°C |
| Typical Boiler Temperature | 220°C |
| Surface Tension, dynes/cm | 37.3 |
| Heat of Vaporization, kcal/g mol | 25.5/250°C |
Applications
SiSiB® PF8704 Diffusion Pump Fluid can be used in a variety of applications including: Aerospace, Electronics, Metallurgy, Vacuum Coatings, and Atomic Energy etc.
Packings
SiSiB® PF8704 is supplied in 5Kg pail, 25Kg pail, 200Kg steel drum, for more details, please visit Packing Centre.