Technological revolutions are funny things. When they first appear, we say "isn't that interesting" and then a few years later, we are amazed at how much the world has changed. The truth of course is that they crept in on us on little cat's feet and suddenly turned into tigers. Two of the most significant so-called revolutions in the last 50 years have been in materials and electronics, and they have aided and abetted each other to the point that the world as we now experience it is a reminder of what Arthur C. Clarke said "Any sufficiently advanced technology is indistinguishable from magic". Relatively few compounds exhibit thermal conductivity while remaining electrically isolating. Foremost among these materials are compounds based on Boron Nitride (BN).
The Momentive scientists were able to demonstrate filler levels as high as 60 wt % and thermal conductivity, κ, approaching 6 W/mK using BN grade PT110. This grade is a high purity single crystal platelet material with an average platelet diameter of 45 micrometers. Because the platelets have a high aspect ratio, flow orientation can be used to achieve high conductivity in the flow direction. Raman et al. at Momentive Performance Materials was able to predict the thermal conductivity accurately without the use of any fit parameters as well.