Elastomer compatible with methylamines
Elastomer compatible with methylamines
(OP)
Hello,
I am having problems with some valves on tank containers transporting anhydrous methylamines (MMA, DMA and TMA).
These valves have internally some encapsulated o-rings (silicon inside, FEP outside).
After some months seems the methylamines have permeated the FEP envelope reacting with the silicon. In fact they had originally a round section and they have became square with the shape of the available space. This is causing some leaks.
We are now searching for an elastomer compatible with methylamines, but we have found contradictory information about this issue. According to some realiable sources seems EPDM or EPR may be suitable. Can anybody with experience on methylamines confirm whether this is right?.
Thank you in advance for your help
Best regards
I am having problems with some valves on tank containers transporting anhydrous methylamines (MMA, DMA and TMA).
These valves have internally some encapsulated o-rings (silicon inside, FEP outside).
After some months seems the methylamines have permeated the FEP envelope reacting with the silicon. In fact they had originally a round section and they have became square with the shape of the available space. This is causing some leaks.
We are now searching for an elastomer compatible with methylamines, but we have found contradictory information about this issue. According to some realiable sources seems EPDM or EPR may be suitable. Can anybody with experience on methylamines confirm whether this is right?.
Thank you in advance for your help
Best regards





RE: Elastomer compatible with methylamines
ht
Seems to back up what you said. Fluorocarbons are fine but silicones not. I guess you need a 100% fluorocarbon o-ring or one made of the other compatible elastomers listed.
Chris DeArmitt PhD FRSC CChem
RE: Elastomer compatible with methylamines
RE: Elastomer compatible with methylamines
Be careful with EPR - this typically suggests that the rubber is blended with other polymers, again typically nitrile rubber, which might not work out so well.
RE: Elastomer compatible with methylamines
In fact is from air liquide where I obtained this information. It is very helpful to see that Parker fully agrees with EPDM suitability.
Anyway if anybody has field experience with these methylamines I would highly appreciate to confirm EPDM suitability.
RE: Elastomer compatible with methylamines
Your information about Parker handbook has been very useful. We are finally going to EPR as Parker recomends.
Thank you very much.
P.D.: difference between EPDM and EPR
www.darcoid.com/images/uploads/pdfs/EPRvsEPDM.doc