TPEs - Yellowing

Hello,

I've recently been cast into the world of injection molding and wondered if anyone could offer some insight into one of the challenges we've encountered. This is probably going to be a stupid question, but here goes:

One of our products is a carbonation vessel with a threaded cap, injection molded using a thermoplastic elastomer (NEWMAT "Easiprene" SBS/SEBS). It is used primarily in restaurant/bar environments, so it's exposed to all the imagined elements. We've been very happy with the functionality and white/natural color aesthetic with one exception - after a few months they begin to yellow, sometimes drastically, which leads me to my question:

Are there other TPEs we could use that resist this yellowing effect, or is it almost always a feature of additives, stabilizers, etc.?

Any suggestions or keywords you could throw my way would be much appreciated.

Thanks so much

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