[Xringer]

When I used to build electronic stuff for the Man,
I used Heat conducting/insulating epoxy,
to stick heat sinks on top of chips and 'canned' ICs that needed cooling.

It was great stuff, but when I needed some, the adhesives shop had to make it special for me.
When I picked it up, I had 2 hours to apply it, and then board had to be baked of hours in an oven, to cure the epoxy.
After cooling overnight, it would take dynamite to remove those heat sinks..

That was great stuff, but I only used it because I wanted insulation too.
If you don't mine electrical conduction, there is cheaper stuff around.
Some is sold in syringes for use by CPU hackers. But some of that isn't real cheap.

I've used JB Weld on heat sinks and had it fail after long 180F runs..