Degradation
The main visible effects are a chalky appearance and a color shift. The component surface may also become brittle. I can vouch for these effects as found in my children’s red polypropylene (PP) monkey bars. After a few years in the garden the extruded pipes retained their full color, while the injection molded clamp parts became white and cracked. Other components likely to be affected by solar exposure include stadium seats, outdoor furniture, greenhouse films, window frames and automotive parts.

Some plastics have been exposed to much harsher radiation levels than we experience on earth. Components in the Hubble Space Telescope (HST) and the International Space Station (ISS) require plastics that can survive the demands of outer space. Fluoropolymers such as FEP and polyimides like Kapton are plastics which have been successfully used for the HST and ISS.

The above effects are predominantly in the surface layer of the material and are unlikely to extend to depths above 0.5mm into the structure. However, stress concentrations caused by the highly brittle nature of some commodity plastics may well lead to a complete failure of the component.

Benefits
Many of us will be using of the main benefits from UV radiation of protective polymeric coatings, such as polyurethane-acrylates, on exterior automobile components, which have been cured by UV. A more local benefit for many people will be the UV radiation in counter top purifiers and water coolers which is often assisted by the good transmission properties of FEP (Fluorinated Ethylene Propylene) tubing and its ability not to degrade. Melt-processable FEP is also used as a protective coating on UV lamps for electronic fly killers, where the coating allows for excellent transmission (only around 4% loss for a 0.25mm film). There are also many applications for UV, including curing of inks on plastic substrates, and UVC radiation for sterilization of components.

UV Resistance at Zeus
Zeus tubing is virtually unaffected by weather or prolonged exposure to ultraviolet light. Where applications demand complete dependability in these conditions, fluoropolymers are the answer. Resistance to extreme heat, cold, and ultraviolet light encountered in radar and other electronic components, such as antenna bushings, are excellent examples of the value of this material in these applications.

Ultraviolet transmittance can be another useful aspect of fluoropolymer tubing. While levels of UV transmittance vary among the fluoropolymer resin family, Zeus tubing is used in applications such as water purification with excellent results. Crystallinity and wall thickness also affect the level of transmittance tubing will allow.
 

Request Samples and Tech Info
If you would like samples of our fluoropolymer or other engineered tubing, or would like to discuss a specific application, we'd like to talk with you. Zeus has a generous sample program, making it easier than ever for engineers and designers to get stock and custom samples quickly. Click here to contact us now.

"Offering custom Teflon® tubing and Teflon® heat shrinkable tubing as well as tubing and heat shrink made from fluoropolymer resins such as PTFE, FEP, PFA, ETFE, PEEK, and more."