It's a relatively soft plastic and I don't think you can realistically build a uniform, good-looking layer that's 1/8" thick, if that's what you mean. If you need that thickness, high hardness, and nice appearance, I think your best bet is just a sheet of glass or acrylic on top.

It can be used as protective varnish, but that would be a very thin layer, probably 0.1 mm or something like that.