One of the things I took from this is that it explains why PLA gets so brittle sometimes. Basically, if it’s wet and hot at the same time it hydrolyzes, becoming one of the manufacturing precursors. This process causes it to depolymerize, so it literally breaks the polymer chains.
With this tidbit of info, it follows that:
Everyone’s PLA 3d prints should be measurably stronger if they dry it before they heat it in the 3d printers extruder.
It would be really interesting if someone were to test this. The problem is that “dry” in terms of PLA means getting it down to about 150ppm of water (as per the Natureworks data sheet). A typical filament dryer can’t do this. It will require a “Dessicant Dryer”.
So, even though it isn’t impossible, it is a challenge. I’m willing to wager that very few strength tests on PLA parts have been done with filament that is dried properly.
It would also be interesting to include Annealing the part. Here’s a good article on the annealing topic, with data. https://www.sd3d.com/annealed-pla-parts/