Why does TFA turn light brownish a few days after opening? Is it still okay to use it ofr synthesis?

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Paul Milham

TFA is a strong acid and may have attacked the rubber

Hellen Nalumaga

Yes, you are right. It also affected the bottles of the other chemicals it was stored with.

i will just have to buy a new bottle.

Carlos Araújo Queiroz

You may want to check the appended technical-commercial document, issued by Halocarbon Products Corp.: