[Steve C.]

Viton material is not blue !

https://www.globaloring.com/oring-colors/


Viton seals: What are the differences in color? Green is the color of choice in Europe for color coding Viton, whereas brown is the color in the US.
Sometimes black.

Viton is a duPont trademark for a specific fluoroelastomer polymer (typically abbreviated as FPM) made with vinylidene fluoride-hexafluoropropylene copolymer - the so-called Viton A resin. Magnesium oxide (MgO) is added as a proton (acid) acceptor to react with the small amount of HF that results from polymerization of the resin. MgO is brown, thus an excess of MgO causes the finished product to be brown unless sufficient carbon black is added as a colorant

http://franklin.chem.colostate.edu/glassguy/viton.html




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