What happens when you heat foam core board up to 100 degrees C?

What happens when you heat foam core board up to 100 degrees C? Will it hold up? Can I use it as insulation under my heated print bed?

Stay tuned for test results.

The HPB is running between 95 to 100 degrees C. When I moved the thermistor to the top side, between the wrench and the foam board, it read a steady 47 deg C.

I added a second layer of foam board on top of the first. The temp in the middle of the sandwich is about 70 C. The temp of the top surface is around 42 C. I’m surprised that doubling the insulation thickness had that small of an effect on the cold side temperature.

The final result is here: https://plus.google.com/105815581544977382868/posts/baRpU2Uxy4Z
I couldn’t add a picture to this post.