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Engineer turns plastic into bricks that are reportedly stronger than concrete

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Re: Engineer turns plastic into bricks that are reportedly stronger than concrete

#51

Post by jerrysievert »

iancmceachern wrote: post #43
SCAQTony wrote: post #14

Earlier quoted context omitted.

The bricks will aspirate toxic chemicals when exposed to direct sunlight: "...Plastics leached twice as much pollution in sunlight as in darkness, they found. One bag leached 263 different chemicals in the dark but more than 13,000 when exposed to light! Others leached even more. And the longer bags were exposed to sunlight, the more chemicals they leached. ..." https://www.sciencenewsforstudents.org/article/everyday…

They could paint them once installed, like nearly every building on the planet. Simple problem, simple solution.

> They could paint them once installed, like nearly every building on the planet. Simple problem, simple solution.

perhaps with a lead paint! that'll make everything better.

"sealing" a toxic material is not a solution when that seal can be broken by scraping it. let's face it, this is a toxic material that doesn't belong in our homes or our society.

Re: Engineer turns plastic into bricks that are reportedly stronger than concrete

#52

Post by ajsnigrutin »

aliswe wrote: post #41
shadowtree wrote: post #10

This is a great way to get microplastic through abrasion into even more places within the foodchain. Wonder if it burns nicely too, plastic after all is "frozen gasoline" - here mixed with sand. /debbiedowner

Asphalt also emits microparticles during wear and tear, as do tires... It needs to be tested, not assumed.

Aren't a lot of those microparticles just sand? Asphalt is basically just rocks/sand and some tar-ish cemicals to bind them together.

Re: Engineer turns plastic into bricks that are reportedly stronger than concrete

#53

Post by recycledmatt »

monkeybutton wrote: post #25
SCAQTony wrote: post #14

Earlier quoted context omitted.

The bricks will aspirate toxic chemicals when exposed to direct sunlight: "...Plastics leached twice as much pollution in sunlight as in darkness, they found. One bag leached 263 different chemicals in the dark but more than 13,000 when exposed to light! Others leached even more. And the longer bags were exposed to sunlight, the more chemicals they leached. ..." https://www.sciencenewsforstudents.org/article/everyday…

How does one even begin to address concerns about toxicity with so many different chemicals? Go in order of concentration? Most to least likely to be biologically active based on models? Cluster them and evaluate the clusters?

Depending on the stream (source) and chemistries there are ways to separate out plastics of concern (POCs) but they aren’t fully at scale yet depending on stream. It’s also very hard.

You go by separating valuable fractions out first.

Re: Engineer turns plastic into bricks that are reportedly stronger than concrete

#54

Post by rockinghigh »

aliswe wrote: post #41
shadowtree wrote: post #10

This is a great way to get microplastic through abrasion into even more places within the foodchain. Wonder if it burns nicely too, plastic after all is "frozen gasoline" - here mixed with sand. /debbiedowner

Asphalt also emits microparticles during wear and tear, as do tires... It needs to be tested, not assumed.

Most tires are made from synthetic rubber which also derived from oil.

Re: Engineer turns plastic into bricks that are reportedly stronger than concrete

#56

Post by Vladimof »

jazzyjackson wrote: post #47
kaetemi wrote: post #44

Can they be recycled, or is it another dead end? Trash brick projects are popping up every few months or so. It seems more like a cheap filler material than a sustainable product.

if it's a brick, couldnt you recycle it by using it wherever else you need a brick?

> if it's a brick, couldn't you recycle it by using it wherever else you need a brick?

that's re-use and that's even better then recycling

Re: Engineer turns plastic into bricks that are reportedly stronger than concrete

#57

Post by keithnz »

throwaway0a5e wrote: post #4

But is it cheaper? (or could it be) Wood, stone, pretty much everything is stronger than concrete. We use concrete because it's strong enough and cheap (and doesn't rot like wood, but a lot of things don't rot so that's not too novel).

they say 25% cheaper than concrete. The video posted in another comment (https://www.youtube.com/watch?v=iFcPqXxAUWM) has a lot of details

Re: Engineer turns plastic into bricks that are reportedly stronger than concrete

#58

Post by blblb123 »

wardedVibe wrote: post #42
blblb123 wrote: post #39

Quoted post unavailable.

lead is just a metal... Microplastics can be much smaller than sand, and may play a role in persistent inflammation*, though really, we just don't know yet. The safe default assumption is maybe don't spill massive quantities of a completely novel compound into the entire biosphere. Its an action we can't undo and will have implications for generations. * https://www.sciencedirect.com/science/article/pii/S004896971...

No post body was provided.

Re: Engineer turns plastic into bricks that are reportedly stronger than concrete

#59

Post by echelon »

armitron wrote: post #38
echelon wrote: post #34

Earlier quoted context omitted.

Which deadly diseases has plastic been linked with? Is the endocrine content of BPA any worse than drinking soy milk? Bioaccumulation of microplastics may be a different story. It may pose an inflammation risk, serve as a safe harbor for bacterial colonies, or be carcinogenic, but as far as I'm aware there haven't been any studies showing this.

Because we need studies (ideally, funded by the same corporations that poison us) to tell us that having increasing quantities of plastic in our blood, lungs and other organs is bad. What happened I wonder to the precautionary principle? Maybe that's going to be our collective lamentation when we crash at warp speed into some sort of great filter.

I get the skepticism, but reality is complicated.

Plastic saves lives, conserves energy, and makes the economy faster and better. Outright removal will be nothing short of impossible.

Consumers don't want to be inconvenienced. Starbucks couldn't even keep non-plastic straws on without a massive amount of customer complaints.

Plastic alternative materials science has a long way to go to even meet the same needs. There are some interesting developments with wood and ceramics, especially in the building world, but plastics are and were nothing short of a miracle.

Unless the number of deaths directly attributable to plastics crosses some alarming threshold, nothing will be done. People would rather go about their daily lives.

It's kind of like how people continue driving cars, flying, and using coal-fired electricity despite being warned of global warming. It's not going to change until people really feel it and demand it. They'd rather keep using their iPhone and read about the issue on Twitter.

Re: Engineer turns plastic into bricks that are reportedly stronger than concrete

#60

Post by scythe »

Unfortunately I think that the frequency of stories like these happens because people incorrectly assume that plastic is cheap and plentiful. I learned this because of a paper about remarkable properties of an alumina-PMMA composite: when I investigated the material costs, I learned that PMMA (aka acrylic) was more than half of the price, even though it was only 20% of the composite by weight.

Plastic has always been a suitable building material. But it's expensive to produce in bulk. It just happens that a fraction of a gram of polyethylene can still make a useful grocery bag, which leads to there being a lot of small pieces of plastic scattered all over the world.

As a method of waste management, this could prove useful. But 500 metric tons of plastic bricks per year (the supply of waste from the article) will only build a few houses, and won't make a noticeable dent in the demand for building materials in Nairobi, a city of millions.

The most interesting variant of polymers in construction I've heard of is the use of fiberglass-reinforced polymer rods as rebar in reinforced concrete. This should be more corrosion-resistant than steel, allowing reinforced concrete structures to last longer. This allows you to use smaller amounts of plastic to make larger amounts of buildings.

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