Thermal Debinding and Filamet™

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This paper provides incredibly precise information on how we remove the thermopolymer binder from 3d prints made with Filamet™. The paper is actually a detailed study on how heat effects PLA, but it happens to apply perfectly to our thermal debinding operations.

Please read, study, share, and repeat!

Here’s the whole PDF:
PLA Debinding Paper.pdf (1.9 MB)

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thanks you ,
very interesting study, they go very far into the details !!
surprisingly the process starts at low temperature :
"First was the evaporation of water and methanol impurities (∼347 K = 73.8 C) followed
by lactic acid (∼459 K) and probably lactide (∼612 K)

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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/

-Brad

hi Bradley
you mean brittleness after part is printed right ?

how about the bed itself ? most of 3d printers do not have a containment chamber ( enclosing the bed) to maintain a stable temperature during printing. it may also influence the strength of parts.

drying PLA before printing ( with typical filament drier ) + a stable and controlled temperature at printing area could may be do the job without a dessicant dryer ?

a too quick cooling will trap the water (or other) particles inside the part… leading to a defective structure ( among other brittleness, but i think it also depends on the material used) . i use what is left of my welding knowledge…it is old and might not be all accurate haha

I just noticed your post. Sorry about that, I’ll set up my notifications better.

What I’m picturing is keeping the filament itself very dry before it’s heated in the the print extruder. I guess it’s easier to just say that it should likely be set up exactly like the manufacturers Technical Datasheet for Ingeo 3d850 from Natureworks. If you buy PLA made in North America, there’s at least a 90% chance that this is the material you’re working with. They set up manufacturing close to the corn fields in the mid-western United States.

Here’s the TDS. I think if users were to dry their filament to these specifications (dp of -40) they would likely get parts that out perform those printed from un-dried filament. You would need to do a tensile test to prove it, but it sure would be interesting.

TechnicalDataSheet_3D850_monofilament_pdf.pdf (86.9 KB)

This one talks about annealing also.
ProcessingGuide_Best-Practices-for-Ingeo-Processing_pdf.pdf (80.2 KB)

-Brad

Here’s more info from NatureWorks. We use 3D850 in our materials. Moved to that from 3032 about 6 years ago, it was a major improvement.