Dear Con

It depends what kind of glue it is. Let's just talk about the really sticky ones that when you squeeze them out of a tube they stick to practically anything.

Most glues are plastics that are made up of giant molecules that are dissolved in a liquid so that they don't stick to anything. But when they are squeezed from the tube and the liquid dries up they stick.

They're a bit like spaghetti noodles. If they're in a nice tomato-ey sauce then they're not sticky at all. But if you leave them by themselves to dry out overnight the next morning they are stuck together like glue in the pot.

Most glues like this are dissolved in a liquid that evaporates quickly. That's why they often smell so bad and you should only use them in a ventilated place.

There is another type of glue that has small, simple molecules while it's in the tube. But as soon as it's out of the glue and exposed to the air, the little bit of moisture that's always in the air makes all the little molecules join together into long strands (again, like spaghetti). These strands get tangled up with each other and everything they touch. So they'll stick different things together.


Yours sincerely 

Virginia R. Claire


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