Polymers in low temp applications

[filterman]

I have an application in which I have to filter ammonia at -50 to -70 F. I have concerns in which these temperatures are below the Tg of Polymers such as Polypropylene, Polyester and Cellulose which are used as filter media. Would building a differential pressure across the media by the flow of the fluid cause any issues.

 

[patprimmer]

You would have to consider the design taking the pressure and material properties at that temperature into account.

Can you get tensile strength, impact, fatigue, elongation and modulus figures for the fibres at those temperatures.

HDPE has relatively good low temperature properties.

Regards
pat pprimmer@acay.com.au
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[gambro]

Filter Media made of expanded PTFE (Trade name Gore-Tex) should do your job very well. Contact Gore for more information.