High-Density polyethylene (HDPE) and high-density polystyrene (HDPS) can handle high temperatures and could be used for coating your pyrolysis reactor. Also poly-chlorinated (or poly-florinated) polymeric materials can handle such high temperatures.

I would also advise that you put some insulation (foam) between the metallic structural material of the pyrolyzer and the over-wrap layer of HDPE or HDPS.

Hope this answer your question.

Professor Yehia Khalil

Yale University

USA

 Polymethylpentene or Polymethyl metha acrylite  (PMMA) may be suitable option for your application or you can use double layer or sandwich structure of silica layer with HDPE.

What sort of temperatures are you talking about?

Hi Juan Proano,

I am working on between 400 C to 800 C..

On the surface that needs to be coated?

There is only a few polymers which are stable in 400deg... And I think that polymeric material which can stand 800deg is not really existing so far.

Is this coat for passivating the surface? If so, you have better choices than polymers. I dont fully understand your need.

Dear Asif:

Can you explain why you need

a polymer

transparent

and coating (for what purpose?)

You already answered for the temperature range 400 to 800°C.

As said by Daniel Pawlak, I think that almost no polymeric substance should support long time contact with a pyrolisis reactor working well above 400°C and remaining transparent!

I think you should conceive a different design with other type materials...

Kind regards

Daniel

Thanks! 

I can not reveal the details of my exp due to IP issues. But if it is not possible to obtain such material then I may have to redesign my scheme.