Advice on plastic to withstand cryogenic temperatures

[sunseeka]

I have a project that needs a replacement for heated glass window panels in a cryogenic chamber. Material will be routinely exposed to air cooled to temperatures as low -120°C/184°F. Any thoughts or advice would be welcomed?

 

[TugboatEng]

Are you replacing the glass with plastic? What is the trouble with the glass? Otherwise, low temperatures don't seem particularly problematic for plastics, including polycarbonate.

 

[Compositepro]

Plastics have a very high coefficient of thermal expansion compared to metals or glass. This can lead to cracking or warping due to internal stresses. Multiple layers, with air gaps, of glass, or even plastic, may be a better solution.