?? the difference
between a urethane clear and a polyurethane clear? Which is the best overall?
This is from the Dupont tech sheet "Understanding Paint Chemistry". I would think the same would apply to clear coats. As I understand it, both are similar except acrylic urethane is an acrylic binder combined with an isocyanate hardener. A true polyurethane (i.e. Imron) is a polyester binder combined with an iso hardener. Of the two, polyurethane is harder and more durable.
Polyurethane has also become a very generic term describing a very wide range of products....some good and some inferior.
I think most modern automotive clearcoats are acrylic urethane. If you get more specific about which clears you are considering, someone on this site could give you recomendations.