Of these, only those that contain an ultraviolet inhibitor can resist prolonged exposure. Some clear or white plastics, such as, nylon, polyethylene and PVC, have very little resistance to UV sun damage. Any resistance they may have is generally connected with their thickness. If you must use these plastics in direct sunlight, a light sanding followed by a layer of paint will provide some protection from UV damage.
Some plastics contain a carbon based pigment for UV protection.
They are generally gray or black in color. However, dark color does not always offer total protection. Black polyethylene plant pots resist sun damage while black polypropylene rope may not. To be certain, look to see if anyone else has successfully used the particular plastic in an outdoors setting before incorporating it in your design. If you have any questions or comments, don't hesitate to contact me via email.