From what I can see, when wood is heated enough in a vacuum, it will not even display the usual signs of melting. i.e Solid, partial solid, liquid.
Instead it will just 'evaporate' and the only substance left would be carbon powder. Which as you might know has a much higher thermal threshold.
Of course, you must know this from school. How do you think fossil fuels are created? LOL, what we are talking about here is charcoal. (or just a bit further on from that.)
I can show you a picture of carbon in a powder form if you like.:p
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