Answer:
Dear Sun 'N Fun, UV stabilizers act like sun screen for plastic parts. They're common and they're necessary for any plastic part that will be in direct contact with sunlight. They protect the part's properties and help it retain its original molded color.

A good example of a part application using UV stabilizers is on p. 1 of this issue of Resin Source. This molder had to produce a polypropylene part for use on the deck of a boat - a tough application for sunlight if there ever was one.

Any part that has color will fade from exposure to sunlight, and the UV package prevents that. The amount of stabilizer used varies, depending on the part's exposure to the sun. Higher percentages can be added depending on the application; again, just like different SPF values of sunscreen.

The Plastics Group custom-compounds and formulates UV packages into its materials. UV packages can be added to virtually any type of resin provided. Costs vary depending on the specific application. Keep in mind that cost is proportional to percentage used.

David Peterson, The Plastics Group's Quality Control Manager, says that anti-oxidants are often added to UV stabilizing packages to enhance thermal capabilities of the product and to stabilize all physical properties. "Anti-oxidants help prevent plastic part degradation due to heat," he said. "We normally add these to UV packages to provide extra protection from the sun."

It's always a good idea to call your custom compounder at the early stages of your project with questions regarding your part application. They can help you with your specific requirements and provide a level of service not often found when using the "major" suppliers.

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