Deep dive into plastic monomers, additives, and processing aids | Hacker News Reader

Deep dive into plastic monomers, additives, and processing aids

pubs.acs.org

129 pointssizzle62 comments

I expect future generations to harbor a unique and refined fire of hatred for our current plastics obsession. In no particular order:

- We extract oil from the ground, transport it thousands of miles to a factory, build precursors, transport those thousands of miles to other factories, build plastic containers, transport those to yet other places for use, fill them, use them for 10 minutes, discard them, and then transport them tens or hundreds of miles to a landfill (can't recycle them, they've got food waste... or you use a bunch of water to clean them for recycling, but see below). This is insane in any reasonable world.

- Plastic recycling is... a polite lie, at best, and more realistically oil company {marketing, propaganda} at work. Some plastics, some of the time, are recyclable a few times to build a high cost, crap material (and relatively few people want to pay more for worse material to work with). Most plastics, most of the time, are junk and somewhere between "not worth the cost" and "technically not possible" to recycle. We used to (as western nations) stuff plastics in a container, ship it to China, and count it as recycled as soon as it left the port regardless of the result. Now, with China having decided that this was stupid, we ship it to whoever will take it, count it as recycled, and then wonder why we find a ton of plastics in the atmosphere and oceans.

- As we learn more about plastics, most of the stuff that makes them work turns out to be some level of "somewhat toxic to some life" and "really violently toxic to all life." Most of the really nasty stuff simply doesn't degrade in a useful span, so will be with everyone else on the planet, for somewhere between "an awfully long time" and "the remaining span of humans on the planet."

But, hey, super convenient for a couple decades! Can't blame us for making it, right? I mean, there was profit involved - and, more than just profit, convenience. Such profit! Much convenience. All plastics!

I don't mind, quite as much, "durable plastics" that are intended to last for a long while. But the entire disposable, super soft plastic ecosystem? This is going to be very, very hated in centuries to come. If it's not sterilized all humans by then. :/

Plastics that consumers end up being responsible for the end-of-life, those need to go. And if consumers need to have it, at least that plastic-like-material must be fully biodegradable, without nano or toxic byproducts or leftovers.

Plastics that are used for health/industry/logistics, I think those are fine.

At the very least, lets stop doing insane stuff like putting BPA on receipts...

"Biodegradable plastics" aren't much better than "recyclable plastics," in terms of actual impact.

They live in one of two categories, with almost nothing in the "actually useful" region:

- "Super, super happy to biodegrade." In fact, they're doing it before you even get it! The plastics aren't really ever nice to use, because they're chemically coming apart in the store. They're UV sensitive, time sensitive, oxygen sensitive, and are generally about as useful as a DivX DVD. By the time you use it, they're a weird, slightly greasy, weirdly weak mess. They don't work. But, hey, they're biofriendly! Or, not, depending on what, exactly, they degrade into.

- "Biodegradable." Given certain conditions. 10x solar UV for 100 years. High temperatures, sustained for periods long beyond what any compost pile can do. Requires certain phases of the moon, sustained for a year without interruption. They're "Biodegradable" on paper, but in reality you can't tell the difference between them and something that isn't. In a typical landfill condition, they last roughly forever. Remember, in a landfill, newspaper is not biodegradable. You can layers of a landfill by the newspapers and magazines you dig up, fully readable. It's a totally sealed, anaerobic environment. Very few "bio" things work in that space.

If you require "plastics that are full biodegradable, without nano or toxic byproducts or leftovers," you've effectively banned plastics. Which I'm entirely fine with.

What I mean by plastic-like is biodegradable materials that replace a purposely designed subset of these functions of things plastics are really good at:

Waterproof

Variable stiffness - Flexible / Rigid

Airtight

Lightweight

Capable of being colored

Injection Mold process capable

Variable opacity - Transparent / Opaque

I think cellulose/lignin/chitin based materials could replace many of these functions, there's some progress on that front but not nearly enough to chase down plastics.

UV induced degradation isn't biodegradation.

Lets just do away with paper receipts.

Almost 200% of commenters and lurkers on this thread buy dead-tree books on the design patterns and best practices of a javascript framework from 2012. Yeah, not much hope with that here.

Non-recyclable plastic should be banned immediately. The fact that we let it persist is ridiculous. I don't care how much costs go up.

We should also limit the types of plastic to a handful, and they should all be recyclable in-country. If we can't recycle it, ban it. Let it get replaced by glass or metal. Again, I don't care how expensive it is. Just like climate change prevention, it's something that needs to happen otherwise we are killing humanity.

What's the preferred alternative to disposable plastic?

"Not disposable stuff"?

If you've assumed that "Spend a ton of resources making something so you can use it once and throw it away!" is at all sane, there's really not much in the way of argument that you're going to find acceptable.

But fundamentally, we have a "linear waste problem" in society. Things are built with non-renewable-in-human-times resources, used once, and then thrown away - and this model has to die. Across the board.

We live on a finite planet. We do not, as of yet, have any sort of off-planet resource extraction, and I genuinely hope we never manage that (the difference between "We've put an asteroid into orbit to mine resources" and "We've put an asteroid into a country we dislike" is a remarkably small delta-V). We should not be using "disposable" items, and I include an awful lot in that - despite having used some myself (we use disposable diapers for overnight, because cloth simply doesn't absorb enough beyond a certain age, and work to eliminate those as rapidly as possible).

Whatever it is you think you need disposable plastics for, I'm willing to wager that 100 years ago, before the age of plastic, people were doing exactly the same thing you want to do, without disposable things. So they're not required. They may be cheap, the may be convenient, but required, no. They're not.

The mental view of reality required to consider "disposable anythings" as sane is quite recent, and, IMO, quite broken.

> the difference between "We've put an asteroid into orbit to mine resources" and "We've put an asteroid into a country we dislike" is a remarkably small delta-V

We can already put a few thousand atomic bombs, warheads or EMPs there, with far more predictability, more accuracy, lower probability of early detection and, as a bonus, lower costs. We have had planet destroying weapons for over half a decade now; if a nation really wants to end another nation - or most of humanity altogether, for that matter - it wont need an asteroid.

Reusable materials: Metal/wood utensils. Glass cups. Washable containers. Paper. The list is extensive. The only downside is slightly higher cost.

'Slightly higher cost' is usually symptomatic of higher resource or energy usage in the manufacturing process.

OR maybe it is just that the requried industrial layout is not in place yet to make those containers in such a scale. But I think that we need a replacement, and the less plastic we use, more alternatives will appear.

These materials predate plastic and existed when the decision to build out the plastic industry was made.

Capitalism isn't flawless, but it does handle money very efficiently. If, for example, landfill space was in low supply, the cost of waste disposal would go up and consumers would prefer products that produce less waste. Likewise if oil was running out.

Capitalism fails where externalities don't have an immediate cost. The pollutants generated in the production, shipping, and disposal of plastics don't come with financial consequences. Plastic is evidently cheaper than alternatives, so companies who avoid them will be outcompeted by companies that do.

Consumers might solve this by boycotting plastics, but I think wealth inequality won't make it easy. Companies might solve this by agreeing not to use plastics, though I'm not sure about the legality and they still could be undercut by new competitors. Or a government could use taxes to add costs to the generation of pollutants, but that depends on pertinent industries' influence and the government's incentives towards national economic performance.

Exactly, people love to hate on Capitalism, but it is a very powerful tool. But externalised cost is the downfall that governments need to step in and control.

> Exactly, people love to hate on Capitalism, but it is a very powerful tool

Lots of social systems or practices that have earned hated are also powerful tools. Feudalism is a powerful tool. Slavery is a powerful tool.

That's only true if all externalities are priced in.

Possibly - or symptomatic of more subsidies going to the fossil fuels industry than to bamboo forestry.

Citation?

Anything food related should be compostable, including in supermarkets. If it means we can't store food for months, the good. It means we can compost them as fertilizer so the planet is still okay.

Without getting draconian on companies who don't give a shit about anything except for profits, they won't lift a finger to do anything about it.

there are lots, such as paper packaging, paper cups, bamboo (for disposable cutlery, packaging etc) there are lots of alternatives

i guess the hardest is plastic food packaging in grocery stores... that plastic is sterile, lightweight and lasts forever (which is good for shelflife, fuel usage etc)... i wonder what airtight alternatives there for that...

To illustrate: https://greenpaperproducts.com/biodegradable-containers.aspx

From their FAQ:

> Bioresin is a thermoplastic made from organic materials instead of petroleum products. Bioresin is a substitute for PET and polystyrene and can replace polyethylene and polypropylene.

> PLA stands for polylactic acid and is a resin made from corn starch. PLA is used to make clear compostable containers and PLA lining is used in cups and containers as an impermeable liner. PLA is biodegradable, and fully compostable.

> Bagasse is a natural byproduct of sugarcane refinement. Bagasse pulp requires minimal processing and elemental chlorine free (ECF) bleaching to turn it into a woven high-strength paper that is biodegradable and compostable.

Unfortunately, many of those materials are then coated with PFAS:

https://www.webmd.com/diet/news/20170201/many-fast-food-cont...

Which have all of the same problems of plastic.

glass

i thought about that too, but glass is 1000s of times as heavy, and typically recycling it means re-melting which is wasteful of energy and has carbon emmissions problems

as i see it, the only way that would work is if

1. we reused the glass

2. some national system where someone comes by and pick up the glass for sterilization (like those old 50s milk bottles)

3. standardized glass containers that are mandated/traded across industries

and that still doesnt fix the usage of fuels to transport all that glass to and fro...

Compostable items are probably the best bet for many common uses. For instance, in many Asian countries you are served food in a plate or bowl made of banana leaves instead of plastic. In cultures where eating with your hands is normal, you can skip needing flatware of any kind. The other alternative is re-use, like we do with shopping bags. Plastic itself perhaps can be less problematic if disposing it is illegal and re-use or recycling is encouraged and enforceable. But a lot of plastic today is not recycled at all (https://www.nationalgeographic.org/article/whopping-91-perce...).

Paper and mycelium?

US based recyclers sell their plastic to companies that then pay to have it shipped elsewhere for reuse.

Is the theory that the government (or some other entity) was paying those companies to pay to ship the plastic to China for no reason?

(It's very true that most plastics aren't worth much for recycling, but there's considerable use of recycled PETE and HDPE, #1 and #2.)

> US based recyclers sell their plastic to companies that then pay to have it shipped elsewhere for reuse.

Is it really for reuse or is it just burning/dumping far from sight? This is a genuine question.

Why would they pay for it and then haul and dump it somewhere?

Like, I know the person at my county landfill that markets the sorted recycled plastic…

It makes me feel good to know that the container that my cottage cheese comes in can be, "recycled" and thus I feel good buying my cottage cheese. That's worth something, yeah?

#5 is one of the ones that isn't worth recycling.

I'm not really sure what your point is though. My initial comment is about the strange narrative that plastic was getting shipped to China for no reason (it would be cheaper to landfill it here than there, so the whole 'greed' thing means there was probably a reason for it).

I'm saying the false narrative that recycling is done really at all is a marketing ploy to sell more things, while making the consumer think they're making a good choice for the environment. Good marketing!

I imagine a future textbook might read:

The petroleum age:

A period where advances in chemistry and materials outpaced cultural and administrative development. Early on, Capitalism was proven to be the most productive economic system in the war-time economy, but this posed a problem once World War 2 had ended. Western industry pivoted from war spending to consumer spending and the post war period ushered in rapid improvements in quality of life for average members of society.

Unfortunately those gains came at the expense of the environment and are being paid for by the current generation and generations to come. While it took only a matter of years to transition from a war driven economy to one based on consumer goods, it took nearly a century (possibly more) to transition towards sustainable methods of production and consumption.

“Yes the planet got destroyed. But for a beautiful moment in time we created a lot of value for shareholders.”

The only way to end industries that profit off externalities is by imposing Pigovian Taxes AND redistributing the proceeds back to the people. That last part is important to avoid Yellow Vest protests, while making the industry non-competitive with the alternatives:

Non-Biodegradeable Plastics

Factory Farming

Fossil Fuels

Our cars are all built to be locked into the hydrocarbon monopoly. Why not open up to a free market of energy generation with solar, wind, geothermal and nuclear like all our other appliances?

Carbon Tax and Dividend bipartisan proposal, and Alaska’s Permanent Fund, are the two most “successful” examples so far. We need MORE!

Regulating and managing consumer chemicals after the fact is no longer sufficient, and in some cases counter-productive.

For example, bans on long-chain PFASs (Per- and polyfluoroalkyl substances) has meant industry has just switched to short-chain PFASs, which are more difficult to filter out of water:

https://pubs.acs.org/doi/10.1021/acs.estlett.0c00004

We need to establish a whitelist of acceptable compounds and force industry to work within that for anything that will shed into the environment, be exposed to foodstuffs, or be worn by humans.

Until that happens, start with your home.

How many pollutants do you voluntarily introduce into your own environment-habitat?

(And for every pound you buy, several pounds of byproducts are shed during production.)

Hold on. I'll get started on that as soon as I finish my bachelor's degree in chemistry and build a lab where I can test all the substances that I bring into my house. You have such great ideas. No idea why I haven't done this yet.

It's not that complicated. Replace disposable plastics with reusable materials.

You don't need a bachelor's degree.

Look at what you're bringing into your home, go down the ingredients list, look them up.

It will take you about 5-10 minutes per product.

And a couple of minutes more for each of the other causes that we want to make consumers responsible for, e.g. carbon impact, treatment of workers throughout the supply chain, local environmental destruction along the supply chain, etc.

Well, if I know that all that goes into the product... all the supply-chain impacts from all the different components of the product... and i STILL add my dollar-vote... which literally says, "yes, please keep doing this, and i'll keep giving you dollars"... and i am aware of all this happening, this entire picture... how am i NOT responsible, or at least complicit, in the process?

There is no ethical consumption. You can only weigh different evils against each other. Unfortunately you only have extremely limited information and limited energy to do so. It hence makes a lot of sense to let governments handle this for you.

Or just have an independent regulatory body analyze the product ONCE and ban the thing before the manufacturer cooks up a million batches and puts them all out to market. I'm lazy and I'm also not qualified to evaluate the danger of random substances I find in the store.

That's the point, its impossible.

We cannot force individual consumers to become chemists, and interrogate every material they come across.

In many cases the materials are completely unknown. Is the PFAS used on a Big Mac burger wrapper listed in its ingredients?

It's not about "we", it's about "you", and what you choose to do with your life-- right now, not tomorrow or whenever the "consensus" agrees on it, but what you put in your own environment and body of your own volition.

This is why I dislike the current version of 3D printing. All it creates is cheap, poor quality plastic objects more and more. We need organic (recyclable) material that can be manipulated, printed and available just like plastic.

PLA is biodegradable. For the things I print, I usually smooth them with PVA as it's biodegradable. As far as pigments go, I have no clue what's in most commercial stuff I think they're the main caveat for truly biodegradable 3d printing.

It is biodegradable, that is correct, it just takes around 80 years to do so.

Can you justify it?

80 years is not the issue. It's the stuff that will be around forever, and in the oceans, that's trouble.

we consume a credit card worth

Per lifetime? Per year? Per kilogram of food? Can you give a bit more context to this comment?

The claim is that humans consume the equivalent of a credit card sized amount of plastic a week. See this article from ABC: https://abcnews.go.com/US/humans-consume-equivalent-credit-c...

This "credit card" bit got popularized in news media because it was mentioned in this brochure put out by the World Wildlife Fund (WWF) on plastic ingestion: https://awsassets.panda.org/downloads/plastic_ingestion_pres...

Their claim in turn comes from this study from the University of Newcastle that was prepared specifically for the WWF (which suggests a potential conflict of interest), according to the list of references in the WWF brochure above. However, I'm not able to find the actual full paper anywhere, and this page last noted that it was being reviewed for publication: https://www.newcastle.edu.au/newsroom/featured/plastic-inges...

from that abc article

  Since 2000, more plastic has been produced worldwide that all the preceding years combined, and about a third of the plastic ends up in nature, according to the report.

is that accurate...? what changed after 2000 to enable this??

My guess is that emergent economies are seeing more disposable income and the adoption of the same consumerist disposable everything habits, supplanting the lifestyle and economies they had previously. It’s especially bad in countries where environmental regulations and enforcement are far behind while consumption has caught up. You’ll often see this in YouTube videos showing garbage trucks just dumping trash (with significant amounts of plastics) straight into rivers, for example.

I think that the sentence is saying that in the period between 2000 and present day more plastic has been produced in the period from 2000 to -inf. A similar statement can be made about most human industrial products - cement production has a curve that appears to have more area post 2000 than pre.

The human population is much larger and richer.

Per week on average according to a study "K. Senathirajah, T. Palanisami, University of Newcastle, How much microplastics are we ingesting? Estimation of the mass of microplastics ingested.Report for WWF Singapore, May 2019"

Obviously it varies person to person but if you drink water, breathe air or use table salt, you are still ingesting plastics on a daily basis.

>we consume a credit card worth

>Per lifetime? Per year? Per kilogram of food? Can you give a bit more context to this comment?

Everyone has a different line of credit.

It's not only the few grams of microplastic that might be ingested physically.

Rather the consumerism of society which drives demand for the kilotonnes of plastic to begin with.

Plus without exersicing a line of credit it would not be possible to consume more than you were worth.

When the more sustainable move financially, environmentally, and socially is to work toward making consumption an insignificant fraction of what people are worth.

What freightening is that as oil as an energy sound declines so will the price of oil and therefore the price of plastic.

Whether you believe in humans being the driving force behind climate change or not, the fact is oil and its byproducts generate pollution. Pollution that's harmful to living things.

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