What if you could design your 3D print to fall apart on purpose? That’s the curious promise of a new paper from CHI 2025, which brings a serious hacker vibe to the sustainability problem of multi-material 3D printing. Titled Enabling Recycling of Multi-Material 3D Printed Objects through Computational Design and Disassembly by Dissolution, it proposes a technique that lets complex prints disassemble themselves via water-soluble seams. Just a bit of H2O is needed, no drills or pliers.
At its core, this method builds dissolvable interfaces between materials like PLA and TPU using water-soluble PVA. Their algorithm auto-generates jointed seams (think shrink-wrap meets mushroom pegs) that don’t interfere with the part’s function. Once printed, the object behaves like any ordinary 3D creation. But at end-of-life, a water bath breaks it down into clean, separable materials, ready for recycling. That gives 90% material recovery, and over 50% reduction in carbon emissions.
This is the research – call it a very, very well documented hack – we need more of. It’s climate-conscious and machine-savvy. If you’re into computational fabrication or environmental tinkering, it’s worth your time. Hats off to [Wen, Bae, and Rivera] for turning what might otherwise be considered a failure into a feature.
Who needs this?
Most people never print multi material, and this requires 3 (pla,tpu, water soluble pla)… So you would have to have a use case where an item was temporarily needed with the properties of those filaments, live somewhere that actually recycles these plastics, and be inclined to recycle. If you ever needed this item again, it would have been less wasteful to have kept the first print rather than dissolve/dissasemble it.
Besides, pla is already a relatively low impact plastic. Also, why do you need smaller plastic pieces? Recycling facilities would shred the print on their end any way (that is, the recycling places that actually do something with these plastics, rather than throw them out).
This seems like academics spinning their wheels to make themselves feel important. I have a feeling that they would have made a bigger environmental impact by spending this time outside picking up garbage in their neighborhood
I’m gonna go further with it being useless outside of a neat idea/hack.
From what I understand, recyclers will trash any plastics not appropriately labeled so most 3D prints aren’t getting recycled and they probably still wouldn’t if you labeled them because 3D prints are such a crazy hodgepodge of materials and odd mixtures.
Also I’m officially past recycling plastic (as an industry/method of disposal, I still do it to put it into the proper waste stream). We should just be burning it, ideally getting some power, and filtering the exhaust for anything bad.
If we move all put plastics to organic sources, like PLA from corn then burning it is still a sustainable cycle since it just goes to new corn.
If we move all plastics to PLA then they turn to goop in cars, hot attics or even left out in the sun. Did you have a different plastic with a green source in mind?
Yeah, PHA. Only softens above 120C or so, and fully biodegrades in home compost bins. Kind of hard to print, though.
Yeah, I figure there is likely more than just PLA that can be made and just used it as an example. Of course it can’t replace all plastic by itself and that’d be a stupid suggestion.
Neat idea, but unrealistic. We just need to waste less plastic. I just returned from a hike along the west Australian southern coast. The beaches were strewn with plastics from all over the world. I even found a French spring water bottle. So much plastic there is more of it than seaweed, cuttle fish and driftwood. It is very sad to see on such a pristine coastline.
I don’t see how that is unrealistic or how just wasting less plastic would solve the issue any more effectively.
Burning it is already a proven and working method with the main hurdle being PR from what I gather.
Organic based plastics have already been made to some degree and are continuing to develop. It’s also not like Oil based plastics aren’t sort of organic based albeit indirectly, so I wouldn’t rule out additional processes being developed to go from some organic starter to more common plastics though it would likely raise prices.
The main issues after that would be combating normal littering and dumping, which would be a problem no matter what, and figuring out a solution to microplastics.
I want my old AMT Enterprise model to last forever–drink bottles, wrappers—let that biodegrade.
You have to fight—for your right–to greeble
Rapid Liquid Printing (RLP) is a promising enough technology that’ll necessitate more complexity.
https://selfassemblylab.mit.edu/rapid-liquid-printing
There’s always someone short sighted.
If I had a dual extruder printer, I’d print complex supports with this.
I’m sure there are plenty of other use cases, it’s just a matter of knowing this is part of your arsenal and recognize it’s value when the need happens.
I wonder how it holds up in high humidity environments. Would it gradually lose cohesion?
Here in Japan, plastics are ‘thermally recycled’, that means we seperate plastics from other garbage so they can burn it at a higher temperature in their industrial ovens than the usual stuff so it burns cleaner, and use the heat to generate electricity.
There is no care for what actial plastic it is (besides PET that hits a different recycling stream to be made into new drink bottles etc), only that it is seperated from the normal garbage so they can burn normal garbage at a lower temperature to save on fuel gas.
So, at least here in Japan, seperating any plastics bu type is a fruitless endeavour, besides the clear PET bottles as used in carbonated beverages.
“Thermal recycling” sure sounds an awful lot like burning. Trading landfill pollutfor air pollution.
As far as I know, modern plasma incinerators are high enough temperature to consume most pollutants.
Besides, most of my nearest landfills are on fire anyway.
Define “consume”. That stuff doesn’t go poof and magically disappear. It just turns into something else. What are they doing with the something else?
Presumably the harmless gasses are vented and the rest captured or caralytically converted to harmless gasses.
Better than them ending up in the ocean and if plastics move to organic sources it would be net zero pollution.
As long as the exhaust is properly handled then it should be relatively clean and if plastics move to organic sources it’s basically recycling with more steps.
So just burn it without polluting the air, like most thermal recycling plants do nowadays.
In the UK we call that greenwashing, not recycling. It’s limited for contaminated recycling.
This could be the next Banksy artwork. His “Girl With Balloon” that sold for 1.4 million shredded immediately after sale. A 3D print that decomposes could be the next big seller. It could also be the next fraud as well. A wealthy couple pays millions for a sculpture only to have it dissolve over time and the seller/artist no where to be found would be a future scandal.
The expensive art space is basically all fraud and tax evasion already.
I doubt the shredding even hurt the value since it has a famous story and I doubt the rich people trading that garbage care as long as they can use art to flow their money around.
The problem with research like this, and the ideas behind it, is that it’s usefulness relies on there being an assumed “next step” in the process that already exists.
We don’t actually recycle plastic in any meaningful volume.
Sure, we “recycle” it, in some lawyer/marketer definition, but it certainly doesn’t get used to make new plastic things like people think it does. We really only do that with scrap metal, and occasionally paper.
Nearly all plastic “recycling” just burns the plastic to generate a meaningless amount of electricity.
Many of these plastic recycling operations even need external fuel to function, and many(most?) generate less electricity that it takes to run the plant itself.
We need to squash this happy idea that all we need to do is make sure our used stuff goes in the recycling bin and everything will suddenly be fine. Because it is a convenient lie.
Until we can/do ACTUALLY reuse plastics, either directly or as chemical feed stock for new virgin plastic, research like this does nothing more than give people “good feelings” about about a problem that we keep making worse.
We can and do recycle 3d printer filament. You can buy recycled filament, and even just get the equipment to recycle it yourself.
Seems to me it could fit well with supports and early prototypes.
Might be less applicable to finished product, but for more localized recycling (your workshop) perhaps it could useful.