1991 ranger brake problem

It's usually the UV which does the damage, though ozone cracking can also occur. Mostly tyres rely only on the carbon black for UV protection

- I don't know of any other anti-UV additives which are widely used in tyres. Better tyres may however contain (more or better) antiozonants (yes, a real word, and thing).

I haven't come across aftermarket tire covers, but if a tyre is going to be exposed outside for long periods, like RVs and campers, on a first look just to prevent UV exposure they would make sense. They might also slow exposure to ozone by providing a physical boundary, or be lined with something which is more reactive with ozone than tyres - likely, as ozone reacts with most plastics and fibers.

Tyres are made to last for 5 to 7 years, because on a normal car they would need replacing due to wear after this time. However a RV or camper might not need type replacement due to wear for decades, so protection from UV and ozone could save a lot of money.

Whitewall tyres were originally made using zinc oxide as pigment, but they use titanium dioxide nowadays. White rubber is more susceptible to UV than black, because the lampblack or carbon black which makes tyres black also helps protect the rubber against UV.

The carbon black does several other things. It decreases susceptibility to attack by oxygen, increases the thermal conductivity - important to prevent parts of the tyre from getting too hot -, strengthens the vulcanisation, increases the tensile strength of the rubber, and increases abrasion resistance. Whew, good stuff!

Peter Fairbrother

I dunno. I only did a three year (Hons) degree ;) Can do some quantum stuff, and pde's, sometimes, but failed conic sections till years later. Perhaps because they have little to do with chemistry. i digress.

If you keep it to atoms made of nuclei and electrons, without going into the quantum physics but with a little electron cloud handwavium, it can be fairly understandable. But often l o o o o n n g, especially if you include reaction mechanisms.

One of my favourites is when in a house to describe the rooms as electron clouds of atoms, each with one nucleus - just barely visible to scale - in each room.

But even if you do get it all in there, and get it understandable (and correct, of course), does it help the average citizen or even tekki-sheddi? Possibly not. So it squirms back into the murk of knowledge which is never going to be used.

Or gets relegated to Google storage - keep the outline, search for details if/when needed. Especially in chemistry where there are over a billion entries in the Beilstein/Gmelin/Reaxys database...

In places like this I try to curate for a curious intelligent person, with a smattering of science, to feel that I answered a question or they learned something, hopefully light enough to float in the murk... or an outline worth remembering.

Peter Fairbrother

If you keep it to atoms made of nuclei and electrons, without going into the quantum physics but with a little electron cloud handwavium, it can be fairly understandable. But often l o o o o n n g, especially if you include reaction mechanisms.

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I practice trying to make tech understandable but I've given up on trying to simplify the thermodynamics of reactions or solubility enough to explain why they go the sometimes non-intuitive ways they do, entropy in particular.