UV resin/polymer clay eyes sticky

How did you cure the polymer clay? If it's left improperly cured oils or plasticisiers may be leaching into the uv resin (what material is it, epoxy? acrylic?) and causing it to break down over time.

 

It very dificult to test for what happens over time and people who just made something often wants to share their work rithgt away, so who knows, perhaps theirs didn't hold up over time either? Or they were just lucky. Or they used some other brand of clay. Who knows, there are too many variables to say aything for sure.
I will say, though, that condiering what uncured polymer clay does to plastic tools that has been poorly cleaned, of if left on a polystyrene surface, or if left on a laminated tabel surface... Let's just say that to my ears, leaving uncured polymer clay incased in plastic in a finished a project sounds like an exceptionally bad idea.

If the iris was unscured, there is still uncured clay prescent. It's not like the cured clay around it is gong to negate that.
But it could be some other thing in the clay that it reacted too as well. The pigments, perhaps? It's hard to test these things when using ready made products like polymer clay.
Could also be that the uv resin didn't cure all the way through and with time that caused the whole thing to deteriorate.

I have no idea. Mixing materials is always a gamble and require a lot of knowlege and careful testing. Many amature made eyes have had similar problems as the one you describe, so you are not alone. All I can advice is to always test you materials under as controlled conditions as possible before making anything and read up on what can inhibit curing for the materials you use. A common one is sulphur, just to name one example. It interfers with the curing of most silicone and some resins. It is commonly found in, among other things, latex. So using the wrong gloves or using a latex based paint in the same project is a bad idea.

Every time you change a material you need to do new tests.

I know it's not glamourous, but that's the main advice: Test everything, even if a similar product has worked in the past.

 

Best of luck! Hopefully, you can figure out a method that works.

 

uncured components can cause trouble, i made eyes too the same way, but i cure the polymer clay iris, the base ist resin printed. but i made the experience it depends on what uv resin i use, some uv resins keep sticky initially, i am still in the try and error phase actuallly