abstract |
Silicone hydraulic compositions, comprising a polydimethylsiloxane fluid and a phenylmethylsiloxane/dimethylsiloxane copolymer having a viscosity at least ten fold greater than said polydimethylsiloxane fluid and having a molar phenylmethylsiloxane content of about 4.5 percent to about 7 percent are disclosed. The fluids exhibit a reduced viscosity temperature coefficient (VTC) relative to conventional polydimethylsiloxane oils and are useful in hydraulic applications such as viscous coupling and viscous damping. |