3D Printing With Rice Might Be Nice

The United Nations Industrial Development Organization recently pointed out a possible replacement for petrochemical-based polymers: rice resin. A Japanese company makes the material from inedible rice and also makes a biodegradable polymer known as Neoryza, which seems to contain some amount of rice as well. The rice resin contains 10 to 70% rice waste. You can see a video with English subtitles about the material below.

According to the video, there is plenty of waste rice. The resulting resin isn’t as toxic as petrochemical-based plastics and doesn’t consume food crops like other plant-based polymers. The video shows the rice resin being extruded like a normal polymer, so it should work like any other thermoplastic.

The video says the properties are similar to petrochemical-based plastics and no special equipment is required to handle it. They also claim that production is easier because, unlike other bioplastics, they don’t generate ethanol as the first part of the process. Waste rice should be cheap to obtain since it is essentially trash today. We aren’t sure what polymers are used in the 90 to 30% of the plastic that isn’t rice, but presumably, that is being brought in as a raw material.

We’ll be interested to see if anyone tries to make 3D printing filament from the stuff. We know that it is being used to replace polyethylene in furniture. We couldn’t help but think about using waste coffee grounds in 3D printing. If you want to compare this to PLA, we’ve talked quite a bit about the corny polymer.

36 thoughts on “3D Printing With Rice Might Be Nice

  1. It looks promising, but I am leery of the ‘produced from waste should make it cheap’ claims. I’ve heard them before, and seen the result, going back centuries. Find a use for today’s waste, and it is tomorrows limited resource. Gasoline is a good historical case (it was a byproduct of refining lubricating oil with limited use as a solvent) as is corn (maize) ethanol more recently (remember the claims ‘it won’t impact food cost, since it will use what we throw away anyway’?)

    I am also leery of the biodegradable claims. Historically, surprises have occurred. If it is stable enough to be fit for use as a thermoplastic, after all, what makes it degradable on demand?

    1. On degradable you have to ask the question over how long – its not like trees die and disappear at any great rate. So if it is made of polymers that are bio-accessible – so similar enough or even identical to natural ones that something can eat ’em, then it is degradable entirely by nature’s existing tool collection. Eventually.

      As for being produced from waste… It is better to target using a waste product you can’t eliminate than look for ‘virgin’ made/refined to order sources when you can. Even if the waste supply will not be enough to meet the entirety of demand it is much more efficient to make that waste a product and should be cheaper than other sources of supply in the longer term. Petrochemical stuff has only stayed ‘cheap’ because the extraction rate and availability has stayed high – but that can’t keep on forever it is a very finite resource who’s extraction should continue to trend down even before its depleted as new locations do not get regulatory approval to open.

      1. >On degradable you have to ask the question over how long

        I saw a conference talk from someone who works on bioplastics, and this was their main argument for why bioplastics aren’t a solution to the microplastics problem. Apparently in the EU “biodegradable” has very little legal weight to it, and so products that are marked with this may effectively never break down in soils or seawater. Even “compostable” defines how much something must break down within 6 months in an industrial composting system, so if you chuck that item into the sea where the temperature, salt levels, microbial community etc. are totally different it might still last a thousand years.

        At a glance through the material for this plastic it doesn’t really seem to say much about biodegradability, which makes me think they don’t have solid data for it.

        1. > it might still last a thousand years.

          Indeed, though the same is true for natural polymers in the wrong places – it is all about defining what you are after as much as anything though, which nobody has quite decided what it should be… If it breaks into micro plastics easily that are then actually consumable by something(s) in nature with the large gain in surface area for breaking down that far means odds are much better something that can process it will snag some of it.

          Doesn’t mean its going to be quickly removed from the environment and so not a problem though, lots of factors in its favour required for that, just that at some point in a not entirely unreasonable timescale it is likely to be passing through something that can process it. Which is alot better than the plastics that are not digested by anything at all yet – waiting on evolution (or gene editing I suppose) or the exact right environmental conditions to break it down part way into something that can be dealt with from there.

        2. Right? I used a section of “biodegradable” drinking straw to inhibit binding on a chain in my toilet flush reservoir, and despite immersion nearly 24/7, it’s still perfectly intact 3 years later

  2. First, “inedible rice”? I feel that deserved a bit of explanation. Is it just me? Do others who don’t live anywhere near rice production already know that’s a thing?

    1. I know some people who think all rice is inedible rice. But I’m this case I would guess it is either unfit for human or animal consumption or the inedible parts of rice like hulls and husks.

  3. Is biodegradable necessarily the correct goal?

    Hear me out here.

    What if we had a plastic that doesn’t have the tendency to break down into micro plastics and doesn’t leach any sort of chemicals such as plasticizers or colorings. Is that possible? I’m thinking of something that if you bury it it’s basically the same as an inert rock for a really long time.

    If we made our throw-away crap out of a substance like that… think of all the carbon we would be burying. And if that was sourced from plants, which had pulled it from the air…

    Wastefulness that actually helps fix global warming.

    On the other hand where does most of the carbon go when fungi or whatever start eating the biodegradable plastic? CO2 or CH3 right? How’s that helping? And any additives in the biodegradable plastic, where does that go? Right into the water supply?

      1. I don’t know. I’ve asked the same thing in comments here before and someone responded that microplastics have been found in well water near landfills. I don’t really understand how that’s possible though.

  4. Currently, is “inedible rice” normally trash? Or is it returned to the rice patty where it can break down and replenish the soil to support future harvests?

    I’m not saying that using the parts of our food plants that we don’t normally eat to make plastic isn’t a good idea. It certainly beats pumping more crude. But if we have to pump it anyway to make artificial fertilizer what was the point? Perhaps one day we will be putting our food scraps in a second recycling bin for compost. We will also probably need to fertilize with more sewage sludge. Which means we are going to need a way to better stop people from flushing things they shouldn’t that might poison the field.

    1. We already put the food scraps in a second bin for compost, mandated by law…
      Well, at least having a compost bin is mandatory, i don’t think it’s specified anything more than that.

    2. This “inedible rice” isn’t in-field leavings, from what I gather; it seems to be already harvested stuff that’s been ruled unfit for consumption, or some combination of husks, straw, and bran left from processing for food, in either case off-site.

      (I don’t believe that riziculture traditionally involved fertilizing with the leavings, because that role was filled by the flooding that needs to happen for paddy formation.)

      In any case, it’s a big already-available resource; I’m seeing notes of an attempted auction by China of 3.66 million tonnes of the stuff for industrial uses in 2017.

    3. Depends on your country. We already have secondary rubbish bins for food scraps, which is processed by the city. THese systems tends to rely on local government and council, but they are fantastic.

  5. The worst part is like the soy-based wire insulation this runs a risk of getting used where it is an absolutely nightmare hazard. If some jerk had figured out a way to use peanut butter for car body panels we’d have a squirrel=based apocalypse of auto ownership.

    1. The infamous air soluble wire insulation Volvo used for a while. Whatever was used for the plasticizer would evaporate and the solids left behind easily crumbled off the wires. Short circuits everywhere.

  6. Is there nothing we can do to mitigate the problem of microplastics?

    I truly hate that our economy dictates that plastic recycling is not economical. The material can be re-used. many of us on this very site show that. But every item you send out for recycling gets pushed to the next cheapest provider of “recycling” for that material. Until it ends up on a cargo ship going to China or Southeast Asia and ends up dumped or burned there.

    If we’d insist on accountability of our waste handling, and start using things like plasma gasification technology to break down the waste that we can’t recycle into a useable material we would go a long way to cleaning up the planet…responsibly. Not by lining the pocket of some company that insists they will “recycle” that material.


    exactly how do I embed a link??

  7. So what’s it made of? What’s the formula? “Some scientists somewhere made something out of rice” is a pretty useless article. Put up or shut up, I’m tired of this “well maybe” nonsense.

  8. The 3D printing resin PLA is made from corn starch (or other similar starches). I would assume that rice, being a starch, would be included. If that’s true, there is nothing really new here.

    A quick bit of Google searching came up with this:

    PLA is a type of polyester made from fermented plant starch from corn, cassava, maize, sugarcane or sugar beet pulp. The sugar in these renewable materials are fermented and turned into lactic acid, when is then made into polylactic acid, or PLA.

    The biggest problem with PLA is the very specific conditions needed in order for it to be properly composted. Instead of being recycled with regular plastic materials, PLA needs to be sorted separately and brought to a ‘closed composting environment’ as otherwise it contaminates the recycling stream.

    And here’s a good link with more info … https://www.goodstartpackaging.com/guide-to-pla-polylactic-acid/

  9. This “inedible rice” isn’t just piling up somewhere. In a world where literally any avenue is taken to make profits, it is most certainly being sold as feedstock for some other industry already.

    I’m not saying making bioplastics out of it is a bad idea.
    But pretending that it is some magical fre resource is super nieve.

    It was already going somewhere, and that industry will need to find a replacement.hopefully one that doesn’t screw everything up more than the current system does.

    You brought up how ethanol production robs from our food sources, but then you don’t bother to look up where this comes from so you can comment on it?

    1. Ethanol robs food production, blah blah blah.

      We have plenty of wasted fields available that could be growing corn or some other ethanol producing crop. Just push the value of it up over tobacco. Bam! Two problems solved!

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