Every year, billions of vehicles worldwide shed an estimated 6 million tons of tire fragments. These tiny flakes of plastic, generated by the wear and tear of normal driving, eventually accumulate in the soil, in rivers and lakes, and even in our food. Researchers in South China recently found tire-derived chemicals in most human urine samples.
A tire that lasts a lifetime would shed less particles than one that needs replacing every so many miles, would it not?
Not if the way it lasts a lifetime is by being made of the same material that wears off but being made of more of it. 🤷♂️
The amount of time a tire lasts ultimately has fuck-all to do with whether it’s airless or penumatic; it has to do with how much traction it provides and how large/heavy a vehicle it’s supporting. Any tire that is good at its job of providing traction to a big, heavy vehicle like an automobile (and SUVs / EVs / EV SUVs only make this worse) is going to pollute a fuck-ton compared to, say, a bicycle tire or the steel wheel on rail public transit.
Rubber+friction=micro plastics
Rubber is quite literally the sap of a rubber tree. Latex. They mix other materials in with it, but this is one instance where I don’t think the rubber is the issue.
It’s the fillers they put in the rubber; Nylon, Rayon, Polyester, etc.
Tires are about 25% steel fibers, another 30%ish filler materials, and Rubber (either synthetic or natural)
Here’s the problem with tires.
If you want long treadwear, you use harder material. But then you get worse traction.
If you want good traction, you use softer material. But then you get worse treadwear.
If you want a car to perform safely on public roads, its tires necessarily need to wear away as they are used. Electric vehicles are presently even worse on tires, as they weigh so much more than ICE vehicles.
The reason tires need replacing is because they’re relatively thin. Airless tires aren’t wear-less tires.
Not to mention that airless tires make for a horrible ride.
Actually earlier prototypes were wear-less, from both companies that were developing them.
As for the horrible ride, from what I’ve seen, that’s not a problem. But even if it was perhaps that should be solved by other aspects of the car.
There is, fundamentally, one measurement that defines everything about the performance characteristics of a car: the amount of force it can impart on the road (and vice versa). This single measure defines is limits of acceleration, turning and braking. And what determines how much of that force is available?
The tires, and the coefficient of friction of the rubber compound they’re made of, which is directly related to how quickly they wear. Every possible solution that makes tires wear less will also make cars perform worse.
…Well, short of drastically reducing weight (i.e. making a bicycle instead of a car).
…Or swapping them out for steel and running the thing on rails (i.e. making a train instead of a car).