Patent ID: 11908595
Assignee: MOMENTIVE PERFORMANCE MATERIALS INC.
Field: Measurement (Instruments)
Classification: CPC H  C  G | IPC C  G  H

Claim 15:
16. A method of insulating or field grading of high voltage direct current assemblies, comprising the step of forming an insulating or field grading layer in said high voltage direct current assemblies by curing a composition comprising:
a) 100 pt·wt. of at least one polyorganopolysiloxane having alkenyl groups,
b) 0-100 ptwt. of a crosslinker component comprising one or more polyorganohydrogensiloxanes,
c) 0-100 pt·wt. of a filler component comprising one or more reinforcing silicas or resins,
d) >0.1-2 pt·wt. of at least one dielectric active compound selected from the group consisting of oxides, carbides, ferrites or spinels of any of Ti, Al, Zn, Fe or Mg,
e) a curing catalyst selected from the group consisting of 0-1000 ppm of a compound enabling hydrosilylation and 0.1 to 2 wt.-% of an organic peroxide each related to the sum of the amounts of the components a) to d), and
f) 0-50 pt·wt. of one or more auxiliary additives,, said cured silicone composition having a temperature dependency of the volume resistivity in the range of 25 to 90° C. at an electric field of 10 kV/mm to 30 kV/mm, such that the ratio of the maximum volume resistivity and the minimum volume resistivity is less than 10, and the volume resistivity in the range of 25 to 90° C. at an electric field of 10 kV/mm to 30 kV/mm is between 1*1011 and 1*1016 Ohm*cm.