Wednesday, November 30, 2011

Nylon Offgassing Ethylene

Polish researchers have published a letter in Biotechniques discussing ethylene emissions from nylon. Doesn't that strike you as odd?

This emission is important to the researchers and other people performing plant research as ethylene is well known as a plant hormone (and it is effective at the parts-per-billion level or less), so if you are sprouting seeds on a nylon membrane (as is commonly done) and the membrane is outgassing ethylene, then you potentially have a problem.

I'm stuck on trying to identify the source of the ethylene in the nylon however. Nylon, whether through ring-opening polymerization (as in nylon 6) or as copolymerized (as in nylon 6,6) is not made from ethylene, and the extrusion/pelletization of the nylon should heat the material enough to degas any ethylene that is there for whatever reason. The exact nature of the nylon is unknown - it is only identified as "Whatman, Nytran N, 0,45 ┬Ám". The Whatman webpage mentions a couple of items that deepen the mystery: the nylon has a positive charge, and that the membrane is cast. Given all this, I see three possible sources of the mysterious ethylene:
  1. Does the process of charging the nylon introduce the ethylene?
  2. Do the solvents used in the casting process contain any ethylene?
  3. Lastly, I wonder if the source of the ethylene is something as simple as the membranes being slipped into a polyethylene bag as a primary package when they are shipped. The membrane could absorb ethylene outgassing from the bag.
Any other ideas?


Unknown said...

My parents are really into sprouting recently. They do flowers, veggies, anything they can sprout indoors.

John said...

It doesn't seem that the outgassing should affect them - the researchers didn't identify any specific impact of the ethylene on their sprouts, but at the same time, they are being cautious and warning other researchers, which is all a good thing.

Anonymous said...

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