Hull spray painting - 2-pack poly or acrylic paint???

[Cliveshep]

I've got enough 2-pack polyurethane to spray the boat, I previously brush painted it, it stank to high heaven and the fumes got into clothes/skin/lungs and remained on my breath for days. Clearly the stuff is lethal. I want to spray the boat this time but I'm pretty sure this stuff is a big no-no for COSHH reasons let alone pollution of the surrounding environment. There is some Sigma Vikote 56 modified acrylic (whatever that is) on E-bay at a very reasonable price. It appears to be developed for the big ship industry. Does anyone know anything about this type of paint, what thinners to use, eg water, Xylene, acetone, white spirit, and is it at all successful as a top coat on a cruiser.

 

[sailorman]

acrylic is too soft
my boat was sprayed 8 yrs ago with Awlgrip poly ( still as new ) the transom was done with Awlgrip acrylic as it can be "burnished", it goes dull & when polished it comes off on the cloth.
the 2 pack poly is unbeatable by any paint system

 

[Pasarell]

Most 2 pack polyurethanes are isocyanate cured. Absolutely fine when brushed (don't understand your comments about the fumes unless you were indoors with poor ventilation). When spraying 2 pack poly, however, you need good extraction and the fumes should be scrubbed to remove isocyanates. If they are breathed they can paralise your lungs! Anybody in the spray booth should wear an airfed hood. For obvious reasons you shouldn't spray outside where others can breath the spray mist.

Despite complex conditions for application a 2 pack poly will perform much better in the marine environment than an acrylic. Polyurethane is much harder and will retain gloss and colour better than an acrylic.
I would go for a brushed polyurethane finish in preference to a sprayed acrylic on a boat