[adrian_b]

I have not seen the paper, but the process almost certainly does not use any glue.

It must use wood compression at very high pressures, which collapses the cell walls in the wood and results in a densified high-strength wood.

There have been various methods to make densified wood for structural applications, but I assume that this is an improved process, which makes an even denser and more homogeneous material, which ensures that even blades can be made from it.

Edit: According to Phys.org, the improvement over the previous processes is a treatment in a chemical bath that removes the lignin and other components of the wood, leaving only the cellulose, before the compression.

This removal of the non-cellulose components ensures that the densified wood is harder and with less defects than those made with the older processes.