Self Destructing Plastics via Embedded Enzymes | Hacker News Reader

Self Destructing Plastics via Embedded Enzymes

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85 pointsbaybal233 comments

Not enough information here to really pass judgement, but multiple issues to consider: 1) 40C is easily the temperature products will see on a tarmac in Arizona while being shipped cross country. Unless they are working with enzymes with a higher temperature range, this would essentially require a cold chain and limit end-use environments which would be a nonstarter for most manufacturers/products. 2) Most plastics are melt processed (extruded/injection molded) at temperatures high enough to denature enzymes/proteins, I do not see an indication that they are working with a heat stable enzyme, which suggests they are relying on manufacturing methods that are likely to be less economically viable. 3) Enzymes are expensive! Unless they are working with (or are plausibly developing) a cost effective solution, I wouldn't be surprised if their material is orders of magnitude more expensive than commodity packaging plastics.

I can't help but think this and other attempts at biodegradability going to lead to even more planned obsolescence. Things which used to last basically forever will self-destruct with no way to stop it; of course it'll be heralded as the next generation of environmental friendliness, but it's actually a way to keep the consumers consuming and the producers producing (nevermind how much resources get used in the production of these things...)

To be fair, reducing the lifespan from a few centuries to a few decades will not impact most consumers. Especially if we're talking about stuff that'll see very few uses, such as plastic bags.

Things wear out. Thats a natural part of life.

Ensuring that the things wearing out can be biodegradable is a big net positive for society.

Making things more repairable / upgradeable is a good way to make things last longer.

I think that's exactly the point. In this context, planned obsolescence of plastics is the goal, because currently they last much longer than needed. I'm having trouble seeing how this might lead to planned obsolescence of non-plastic goods that you would want to keep around for a long while.

I have some older plastic items that have become very fragile and brittle. They're not lasting forever.

I also left one of those clear plastic tubs where the sun shines through a window on it. After a couple years, the plastic became very brittle, lost its strength, and the tub pretty much disintegrated.

Mercedes tried biodegradable wiring and it totaled cars due to electrical problems. http://www.badmercedes.com/

if by totaled you mean they would catch fire and burn... what a bright idea to use biodegradable insulation...

It forced people to buy new cars. You could even say it was a genius move.

These enzyme-embedded plastics should be the cheapest option, so that all the disposable garbage that gets made would use them as ingredients. Durable / long lasting plastics would cost a premium and only get used for things meant to last.

In general love the idea of these sorts of plastics improvements and hope it can solve a lot of the existing waste issue. And cut down on the awful micro plastics!

But the cynic in me is wondering about the articles 10 years down the road talking about how these enzymes are now basically "salting the earth" and we can't wait to figure out how to get them out of the soil and water.

You're right, best to stick with the good ol' reliable 1000-years-to-break-down pollution

I suspect plastics may become as valuable as oil today in the far future.

Opinions on this?

https://www.youtube.com/watch?v=vdSjyvIHVLw

dumb

If you define far future as far enough then it may well be coal or oil. The same thing with lignin is what made coal - it was a hydrocarbon "plastic" of its day that bacteria hadn't figured out how to consume.

Of course if we assume a remotely industrial era progression of advances oil reserves may be near-worthless. Why dig down say fifty feet for enough oil to fill the shelves of a Walmart camping section?

It isn't an either this or that kind of situation. You're imposing a false dichotomy on the issue.

Just because we don't want to stick with the good ol' reliable 1000-years-to-break-down pollution like the way you put it, doesn't mean we should jump on the first promising path we see. Or else you might find yourself in ten years with all the seagulls dead or something.

That is my worry. They are putting in a development near my house so I'm watching them put in a lot of pipes using a large amount of energy (6 high horse power tractors emitting a lot of CO2 for weeks on end). If those pipes last forever (as currently expected), then overall the impact is low, but if they start degrading we will be spending even more CO2 to replace them.

Though a part of me wonders how much more it would cost to put in a subway when they already have the ground dug up.

Enzymes are proteins. Proteins degrade. Anything is possible, but this seems unlikely.

More worrying would be the by-products of the plastic degradation reacting and producing something harmful.

If it’s economically viable, there is no way that this isn’t used against buyers as part of planned obsolescence schemes.

This will become a prime example of 'being poor is expensive'.

I've changed my mind on plastics. It's not really the plastics that are the problem. It's that nations without good garbage infrastructure are using them, and using them for single use objects. Most of the plastic pollution comes from Asia. The Philippines for example.

The best way to tackle plastic pollution is to properly dispose of it. Not even recycle, just collect it and stop dumping it into rivers.

Even in a European Capital trash is routinely found on the floor, on the streets. People throw it on purpose or by mistake, or the wind blows it away. Eventually it is forgotten, blown to forests to break down, or carried to waterways until it reaches rivers. Let's not pretend that plastic isn't everywhere in the west too. We need to stop single use plastics and unnecessary packaging yesterday.

We need to stop fooling ourselves that plastic is recyclable and is not single use. Dump it in garbage dumps.

Burn it for energy and electricity like they do in some countries. Better that than leaving it to never decompose in some landfill.

This is absolutely false. Rich nations do not know what to do with all the trash they produce. Australia had been shipping their trash to Indonesia, Malaysia and other SE Asian countries [1] for quite a long time, until just recently when Malaysia decided it was enough. Australia is not the only rich country guilty of this.

The diabolical thing is that Australians believed their waste was being handled correctly, e.g not being shipped to poor nations so their rivers and streets could flood with our trash.

The fact remains that plastic exasperates the “disposable” mindset and it produces mindbending amounts of waste every year. Its a logistical and environmental nightmare

[1] https://www.smh.com.au/world/asia/why-australia-sends-its-wa...

> Rich nations do not know what to do with all the trash they produce.

I don't think this generalisation is correct. PG [0] digged up some numbers in a twitter thread:

"The US, Canada, and all of Europe combined account for .87% of plastic emissions. The Philippines accounts for 36%.

The reason the Philippines emits so much is not that it's emitting waste shipped from the US, Canada, and Europe. Even if every kilogram of plastic waste shipped by the US to the Philippines ended up in the sea, it would account for less than 1% of the Philippines' emissions."

[0] https://twitter.com/paulg/status/1389150186283413505

I bought a biodegradable tarp once. It was a big mistake- it fractured into dime sized pieces that were scattered by the wind all over my yard and took weeks to pick up.

Beautiful, love it - let's get on with it already, though. I hate plastic, I love these ideas. Down with plastic, bring back glass for all liquids at a minimum.

How about rapidly biodegrading plastic that most things are made of? Your car or your fridge dissolves in 3 years, so you have to buy a replacement. "Greenness" can mesh very well with greed.

Couldn't we be landfilling all this plastic to capture its carbon, instead of helping it turn back into CO2?

Also worth considering is how this would prevent re-use of products using this material, and uncertainties over the breakdown process (perhaps it becomes likely to stop when it reaches a certain size)

What are the health effects of the monomers left behind by this process?

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