If you want to try it....
use an ablative paint. Thats because the toxicant and carrier are homogeneous and they both wear away. Other type of bottom paints the toxicant would wear away and leave the base coat, which builds up in layers after extended time. The main problem is getting the paint to stick which with a typical bronze blade, it is difficult and requires a primer. But with a plastic type blade, the paint may adhere much better. I would check with the manufacturer of the prop and with the manufacturer of the paint and see what they recommend.I tried using Micron 33 on my bronze bladed prop, but never was able to get a good primer to stay on. Usually it would "chip" off in chunks and barnicles would attach themselves very quickly on the bare metal, resulting in an unbalanced prop. Some prop manufacturers recommend no paint at all, just keep it clean.Let us know if you try it.Ernie