eli5: Plastics are polymers that are engineered to have specific uses for utility. Why can’t they be engineered to be better for the environment?

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I really can’t wrap my head around this. With all the garbage created from plastics, can’t they just design and engineer green versions?

Update: Sorry guys, I know I’m oversimplifying everything here. Thanks for the great contribution. Really appreciate it. I didn’t get the answer i wanted, but it was worth a shot.

In: Chemistry

7 Answers

Anonymous 0 Comments

The negative environmental effects of microplastics were totally unanticipated and still not completely understood. Basically, some of the polymers are close enough to some biological signalling molecules to trigger hormone effects in living things. But, the responses differ across different species, and we’re still not entirely sure what they are even doing inside our bodies to cause negative effects.

We can make different polymers. But making them to avoid a problem that we don’t even fully understand is an impossible ask. And it’s almost certain that any new polymer would cause some sort of reaction in some species somewhere, because biology is just that varied.

Anonymous 0 Comments

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Anonymous 0 Comments

Plastic is cheap and longlasting. Designing it to be environmentally friendly is the opposite of that. Substituting the fossil fuel that its made from with a bio material is more expensive, and designing it to degrade in the environment over time means intentionally design a weaker product.

Anonymous 0 Comments

they are doing exactly that, and have been doing for decades. however, like all things, its a “pick two out of three” kind of thing. very superficially – cheap, green, effective. you get at best two out of three. cheap and green? no problem, recycled plastics or simple soy based polymers. green and effective? can do, but it’s going to require a lot of specialty engineering that may not scale *at all*. cheap and effective? that’s where we are currently at.

a second compounding problem is – it’s not so straightforward what is overall better. if I make a bioplastic that breaks down into neat safe biodegradable building blocks within 2 years, that’s awesome. but it also means that I need to replace whatever it’s made into every two years, every two years I need to input the raw materials and energy as opposed to the (arbitrary number) 10 years a regular plastic may have lasted. and that’s if it can even be replaced. maybe it’s a fitting for say a vacuum cleaner which breaks down, and now people throw the whole cleaner away instead of replacing that one part because people are lazy like that.

Anonymous 0 Comments

One of the biggest advantages of plastics is that they are durable and not biodegradable because that’s exactly what you want in many use cases. They’re also really cheap and easy to produce in large quantities.

Producing plastics that are better for the environment contradicts those advantages. A biodegradable plastic won’t be as durable as a non degradable one. Engineering that hits the sweet spot takes long and is expensive.

I should also note that multi use plastic products are really environmentally friendly in many metrics. They are lighter than most solutions using metal or glass, more durable than most biological materials and use very little resources in the production.

Anonymous 0 Comments

They (chemical companies) most certainly can. For them to do so it must be *profitable* to do so. A company that does unprofitable things quickly goes out of business. For it to be profitable there must be demand. Demand can come about in two ways: either customers prefer the product of their own free will, or government regulation effectively bans the competing product.

Right now there is no demand. People do not know which type of plastic is more or less bad, and there is no ban on the bad types.

Anonymous 0 Comments

I make plastic resin for a living.

They can and they do make biodegradable plastics.

It’s just that they are so expensive to create, release C02, are structurally useless and or limited production due to the availability of raw materials.

You can’t just “engineer” shit. That’s not quite how the world works, else we’d colonize Mars by now. 

Scientists have to find the working principles, we engineers make it practical, useful and in large scale.  We are still looking for that working principles.

Lignin-based biodegradable plastics do exist and are slowly introduced. They come from trees basically which has it’s own economic worries, but it’s carbon neutral during bio degrading 

This plastic though runs into problems though, since current plastic raw material price is low there is not incentive for companies to spend tens of hundreds of millions to build new plants or retrofit existing ones. Since the process is vastly different than other plastics being manufactured. So until petroleum based plastics become too expensive to produce large scale, they’re going to dominate the market