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Nylon 66 and Thermo-Oxidation

Nylon 66 and Thermo-Oxidation


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?

RE: Nylon 66 and Thermo-Oxidation

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

RE: Nylon 66 and Thermo-Oxidation

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!

RE: Nylon 66 and Thermo-Oxidation

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

They can extract all the additives and identify them.

Chris DeArmitt PhD
President - Phantom Plastics LLC

Consulting, ideas and training on plastic materials

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