Are Thermal Interface Materials electrically insulating?

Some TIM materials are electrically insulating whereas others are not. Those with a breakdown voltage on the data sheet indicate a level of insulation. Those materials include the T-P Void / Gap Fillers and the T-P Ins series. Careful consideration is required when determining which material to use should insulation be required. Higher levels of thermal performance can be achieved at a lower price where electrical insulation is not required, through the use of graphite acting as the thermally efficient compound.