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A plastic made from milk that vanishes in 13 weeks

89 pointsby JeanKagetoday at 2:20 PM77 commentsview on HN

Comments

killerstormtoday at 6:46 PM

Any article about biodegradable plastics should start with advantages over cellophane/cellulose.

People have figured out how to make it a hundred years ago, it's already used for food packaging, known properties, abundant and cheap - made from trees / other plants.

The article starts as if it's some breakthrough miracle which is unheard of. I can literally just buy compostable bags for organic waste made of corn starch on Amazon. It's already a product.

Journalist demonstrate less awareness than 8B LLM. Scientist tells you about a new plastic? Ask them how it's better than what's already on the market.

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david-gputoday at 3:26 PM

Milk is surprisingly intensive in terms of greenhouse emissions. It is somewhere around 1 to 3 kg CO2-equivalent per kg of milk.

Milk protein costs around 95 kg of CO2-equivalent emissions per kg of protein, which is apparently what was used in the production of this plastic [1]

[0] https://www.sciencedirect.com/science/article/pii/S002203022...

[1] https://ourworldindata.org/grapher/ghg-per-protein-poore

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lich_kingtoday at 4:48 PM

> vanishes in soil in just 13 weeks.

Part of the problem with waste management is that we don't really put it in the soil. Your household garbage is mostly biodegradable, but if it ends up buried in a lined pit under tons of other garbage, even paper and orange peels will probably sit there for centuries. I'm not sure it makes much of a difference what kinds or quantities of plastic end up buried in the landfill.

I think the solutions here are more on the supply side than the landfill side. The question there is what are we trying to solve.

Energy use? Most alternative packaging materials are energy-intensive too, so it's less about plastic and more about retail and consumer preferences to have everything individually wrapped and packaged in bags or boxes with colorful graphics, nutrition information, and so on.

Environmental pollution? There, the problem is the plastic that doesn't end up in a landfill. Including our "recycling" shipped overseas.

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cestithtoday at 3:44 PM

I’m hoping this is a first step toward using some other protein(s). There are some fairly high protein plants like chickpeas and soy that are less intensive to produce than milk.

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abdullahkhalidstoday at 3:43 PM

> Plastic production has climbed from 2 million tonnes in 1950 to 475 million tonnes by 2022, roughly equivalent to the weight of 250 million cars.

That's 60 kg/person/year of plastic, which is a lot. Or about 4800 kg for a person living 70 years. Obviously, there is wide variation in this number across the human population.

nancyminusonetoday at 4:19 PM

Worth noting that casein is a very very old technology - people have known how to use it (well, milk) to make a type of glue for thousands of years.

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kleibatoday at 3:31 PM

Luckily, producing milk is completely environmentally friendly!

/scnr

abracadanieltoday at 7:56 PM

Products that involve clay as an ingredient tend to have issues with lead contamination (along with other heavy metals) as it likes to absorb them, and the sources are highly variable.

regularfrytoday at 3:32 PM

The paper doesn't talk about thermal properties, which is a shame. Would be good to know if this is a thermoplastic.

wolfi1today at 4:28 PM

sounds like bakelite to me. you can get a disposable polymer from polylactide as well, and it can be obtained from silage (so-called green refinery, although the term seems to have been broadened in the last decade)

tartorantoday at 4:29 PM

PLA is also biodegradable and cheap but it does not biodegrade that fast, certainly does not vanish in 13 weeks. Im not sure what the usecase is here but I'm sure it could have some uses.

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boringgtoday at 3:34 PM

New subscription model coming to plastics! Products last only 13 weeks.

I know - long lived plastics are bad. We need some kind of middle ground thats as cheap as the current plastics and doesn't last as long.

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LurkandCommenttoday at 3:39 PM

Is this going to drive up the price of milk? Corn went up when we started making ethanol from it for gasoline.

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pixl97today at 4:11 PM

How long before a bacteria learns it can eat this and starts breaking it down much more quickly?

1970-01-01today at 3:43 PM

I've said before that we need a short term plastic that completely dissolves into harmless organic compounds that can then be forgotten in nature with no ill effect. 13 weeks is just about right!

today at 3:51 PM

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TZubiritoday at 3:43 PM

>vanishes in 13 weeks

Well then it's not plastic is it? Plastic's defining characteristic is that it is not decomposable

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CagedJeantoday at 6:48 PM

Wow! Temporary boob implants!