why does paint stick and how do paint remmovers unstick it

You'd get a better answer quicker using google.

Maybe for walls but metal would be assumed to be nonporous. There could be chemical interactions with the metallic surface such as oxidation on the surface with maybe hydrogen bonding or chemical reaction between paint and oxide or hydroxide on the metal. If there were an inert boundary layer on the metal like oil, the paint would not stick. Even finger prints can be a problem. To remove the paint, a solvent or plasticizing agent would be required.

As the article says, it's about adhesion. oil-based paints are the gold standard for adhesion to metal.

The cans of rustoleum at ACE adhere to metal just fine.

On Mar 19, 2022, Scott Lurndal wrote (in article<news:vRoZJ.171592$ snipped-for-privacy@fx48.iad):

You seem to know the chemistry well based on your confidence level. Is the paint sharing the hydrogen bonds or the hydroxyl groups? And is the bonding covalent or electrostatic based on your knowledge?

Ron, the humblest guy in town.

My chemistry training is well in the past, but as I recall, the bonds are covalent (chemical) bonds.

Mine is four US patents on adhesion with fibers and resin.

I have taken physics, inorganic, organic and biochem, but I wouldn't say I know what makes paint stick to metal. They never talk about practical things.

IMHO... It's not likely to be covalent bonding though, as heat doesn't seem to be involved and it can be removed without damaging the metal underneath.

It's more likely to be electrostatic, IMHO, given the adhesion factor. Maybe like how scotch tape sticks to metal?

But if someone knows how I would be edified by their explanation of how the paint sticks so tenaciously once it's dried as one or more of the three fundamental forces explained in the standard model are likely involved.

Is it close to whatever makes bathtub and toilet bowl rings? Some weed spray leaves visible marks on the weeds.

A quick Google gives all kinds of answers without specific chemistry but recommend some paints over others which would suggest some kind of ionic or chemical bonding. IMHO while metal surfaces are smooth and maybe shiny they must have some oxide on the surface conductive to ionic or chemical bonding depending on the paint.

You're right about those observations especially about the metallic shine.

Metal shines because it is smooth enough to bounce light back into our eyes. (That's simplified as electron emission energy levels are also involved.)

However metal is not smooth at the molecular level we're talking about. And there is always going to be a metal oxide of some sort to deal with.

Why paint sticks to metal won't easily be found in a search. It's probably answered somewhere but the right page will be hard to find.