Nylon 66 and Thermo-Oxidation

[jmarcello123]

Hello,

I am currently having a problem with Nylon 66 in regards to it changing from a light grey/green to a brown. I was thinking this is due to the fact that I am raising it to 60C for an hour, which is in it's range for Tg. Along with exposing it to a 43C for 7 hours. Could exposing it to these temperatures increase rates of thermo-oxidation. Could thermo-oxidation be to blame for the change in color?

If I remember correctly Nylon's are susceptible to thermo-oxidation due to their carbonyl groups. Is there anyway to prevent this discoloration besides keeping it a room temperature?

 

[Demon3]

Such low temperatures and short exposures should not result in any oxidation. I suspect something else is happening. Is there pigment in the sample or perhaps there's a copper salt stabilizer that is sensitive to temperature. I will ask a friend who is a PA 6,6, expert.

Chris DeArmitt PhD
President - Phantom Plastics LLC

Consulting, ideas and training on plastic materials

http://www.phantomplastics.com

 

[jmarcello123]

Thank you! I do not know exactly what is in the polymer, I work in reverse engineering others products so I'm trying to understand whats in the polymer myself without knowing exactly what it is. Any help is greatly appreciated!

 

[Demon3]

If you want to work out what's in there I use this lab:

http://www.stabilization-technologies.com

They can extract all the additives and identify them.

Chris DeArmitt PhD
President - Phantom Plastics LLC

Consulting, ideas and training on plastic materials

http://www.phantomplastics.com

 

[rickfischer51]

There is a lot of stuff on this topic on the internet. A couple examples below:

http://onlinelibrary.wiley.com/doi/10.1002/pola.1987.080250908/pdf

http://www.angelfire.com/pa5/parag/CHAPTER5/CHAPTER5.pdf

http://sanangelo.tamu.edu/files/201...-the-Brown-Material-from-Oxidized-Nylon-6.pdf

Rick Fischer
Principal Engineer
Argonne National Laboratory