Polystyrene covered with carbon fiber, UV light, weather

I have need to create a piece with carbon fiber over polystyrene core and carbon fiber skins. The piece will be covered with carbon fiber but exposed to the elements - let’s say year round in the sunlight, in the rain, in the snow, etc.

With only UV resistant resin, how would this hold up in the environment? Would the resin yellow significantly over the coarse of a few years? Would any part of it break down due to varying outdoor temperatures? Is oxidation a real concern?

From what I understand, the polysterene should be ok but with any foam, it will shrink slightly so delamination is of a concern. I’m too worried about that b/c of the geometry of the part. I am worried about the resin/carbon breaking down over time or becoming yellow. A tiny bit of yellow is acceptable since pretty much everything dulls in sunlight however, turning very yellow is problematic, especially if some areas are in the shade and some are in the light.

Any thoughts? Are there parts out there that are similar in nature and exposed to the elements? I can think of car hoods, roofs, etc. but it seems like these cars are usually garaged or protected by clear coat or paint.

Where are you located as it is not stated in youe screen name?

Weather climates?

Structually hold up something?

Need more information…

East Coast but the part is going world wide. Of course I want the part to work in the extremes but let’s say basically any weather in the US - I’m not going for extreme Arctic weather :smiley:

Yes, it is partially structural. It’s about 2’x3’ and will flex. I am having it tested structurally but it needs to hold about 300lbs. I can simulate abuse to the piece but not repeated exposure to the environment (yet - I’m looking into weather labs). I need some assurance that I’m on the right path or if I seriously need to look into top coats or an additional layer of glass (or something more UV resistant).