Large polystyrene sculpture needs a tough and hard wearing coat of paint. Using a Cellulose Based Paint is not a possibility because of the small studio space available.
The idea so far is to use something like a builders concrete sealant put first put on the polystyrene and then to apply a water based paint like one that is put on to cars these days.
Does there exist an especially tough and hard water based paint? For instance one that we might think is put on to the bumpers of cars or something else that needs a hard coat? Grateful for any suggestions.