Drip Feed #4: unrepentant nerd-ery

For every influencer trying to convince you that micro and nanoplastics are going to be the death of you, your loved ones, and everything in a 10 mile radius, there’s a stack of research that makes them sound like medieval peasants worrying about the end of days because of an eclipse. But they’re more concerned with selling you something than saying “well, the science is unclear about that.”

At the Right Filter, we focus on the science. Not just because we’re giant, unrepentant nerds, (which we are) but because, if you’re willing to read enough papers, the outlook looks more optimistic rather than pessimistic. So let’s get into it!

First, a team from Washington State University used lingin to substitute 20% of the fossil fuel based chemicals that are used in making polyurethane foam. That’s the foam they make mattresses out of. Since lignin is the 2nd most abundant renewable carbon source, and makes up about 30% of the non-fossil fuel-based carbon on Earth, that’s kind of a big deal for sustainability.

Now, usually, lignin is super difficult to extract from the plants it comes from. Because of that most lignin is either burned to produce fuel and electricity or used in low-value products, like cement additives or as a binder in animal feed.

But this team extracted the lignin with a mild, environmentally friendly solvent, and did it in a way that works better than the current methods. So, double win!

https://phys.org/news/2025-01-based-substitute-fossil-fuels-plastic.html

Next, a team at Cornell figured out a way to potentially solve the issue where tough plastics are harder to recycle. Which is kind of a serious issue because you don’t want a replacement hip to dissolve after it’s been implanted, or a car tire to come flying apart while you’re driving.

The class of plastics used in these applications are called thermosets and they’re known for extreme durability. They also make up about 15-20% of all the plastics made and they are impossible to recycle.

But this team used dihydrofuran, a chemical building block, to redesign how thermosets are made. This new method allows thermoset plastics to be recycled by heating it , after which it naturally degrades in the environment. Which is great!

https://phys.org/news/2025-01-durable-plastic-sustainability-makeover-polymerization.html

Next, a team of researchers from Kyungpook National University found a way to narrow down which naturally occurring microbial enzymes can degrade PET plastics. Now, scientists have already found a lot of these enzymes in bacteria, and they’ve already been modified for industrial applications. But the hunt is time consuming and difficult, so the work by these researchers can actually help us speed that along.

https://phys.org/news/2025-01-enzyme-profiling-method-candidates-plastic.html

Going one step further, researchers from the Horizon 2020 project called PROMICON have developed a method that uses cyanobacteria to produce PHA. Which is a type of bioplastic that fully degrades in soil, water, and marine environments.

Now, we’ve known how to use microorganisms to make PHA for a while, but scaling up its production remains a challenge because of how much water and organic raw materials are needed. But this specific method uses photosynthesis, so it uses sunlight, absorbs carbon dioxide, and doesn’t need nearly as much of those raw materials! And it also doesn’t generate microplastics!

https://phys.org/news/2025-01-highlights-photosynthetic-microorganisms-sustainable-bioplastic.html

Finally, and this one’s my favorite, science is never satisfied with just finding out new stuff, it always goes back and verifies previous assumptions.

See, for decades, polystyrene and polyvinyl chloride has been used in construction pipes, trash bags and credit cards. And for decades, the assumption was that since it didn’t break down in the sun, there wasn’t an easy way to break it down.

But researchers working with the American Chemical Society found that if you turn up the light high enough, and the stuff has enough carbon black, which is a pigment, it starts to break down naturally. Which was news to even the manufacturers of the stuff!

So what they found was that carbon black can depolymerize polystyrene and polyvinyl chloride. Now, the reason that’s important is that these two are the least recycled plastics in the waste stream. Through a process called photothermal conversion, intense light is focused on plastic containing the pigments and that jumpstarts the degradation.

To quote Assistant Professor of Chemistry Erin Stache, "The surprising thing, especially with the black polystyrene depolymerization, is that they've been manufacturing these materials for decades and it seems no one recognized that this was possible.”

So science tells us that things can be better, that the problems that got us here are solvable, and that even the problems we thought we understood can be reexamined.

At least if you’re willing to listen to the unrepentant nerds without agendas.

(if you'd prefer this as a newsletter/podcast: https://therightfilter.substack.com/s/drip-feed)