Teflon radiation stability

Teflon is the most adequate material to build vessels it is totally transparent to the microwave radiation, is resistant to all acids, has good thermal stability, and can sustain temperatures of up to 200°C, as opposed to polystyrene, which is only stable below 70°C. The only one application where it cannot be used is when concentrated phosphoric acid or sulfuric acid is used, since these acids have boiling points far above the fusion point of Teflon. In this case, quartz is the material that should be employed. Another material used often is polycarbonate, which resists the acids very well and has a fusion point of 135°C. 

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