Hydrophobic material to stop frost
Hydrophobic material to stop frost
(OP)
Is there a material or coating that is hydrophobic enough to prevent the formation of frost on cold objects?
One of the challenges with any cryogenic system is that there are always parts that are cool enough for frost to build up. The thing I am looking for is a foam insulation that would shed water to the point that it does not condense on the surface or freeze. Coatings for glass or metal would also be valuable.
One of the challenges with any cryogenic system is that there are always parts that are cool enough for frost to build up. The thing I am looking for is a foam insulation that would shed water to the point that it does not condense on the surface or freeze. Coatings for glass or metal would also be valuable.





RE: Hydrophobic material to stop frost
My advice is not to try, it's not possible.
Chris DeArmitt PhD FRSC CChem
www.phantomplastics.com
Consultant to the plastics industry
RE: Hydrophobic material to stop frost
My experience is that open cell foams are worse than closed cell as you suggested.
RE: Hydrophobic material to stop frost
An interesting experiment might be to coat some surfaces with cooking oil and see what happens.
TTFN
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RE: Hydrophobic material to stop frost
Chris DeArmitt PhD FRSC CChem
www.phantomplastics.com
Consultant to the plastics industry
RE: Hydrophobic material to stop frost
RE: Hydrophobic material to stop frost
TTFN
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RE: Hydrophobic material to stop frost
Mike Halloran
Pembroke Pines, FL, USA
RE: Hydrophobic material to stop frost
The reason for the frost is because something cryo is flowing through them. Therefore, a heater blanket would be contraindicated.
TTFN
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RE: Hydrophobic material to stop frost
Here is one (Vacuum Barriers) of several manufacturers of this type equipment.
http://w
RE: Hydrophobic material to stop frost
This may be counter-intuitive, but a very low- powered heater blanket should be sufficient to prevent frost, without seriously affecting the load on the refrigeration plant. To the extent that the frost compromises the insulation, there may be a net energy saving associated with heating the insulation's surface.
Mike Halloran
Pembroke Pines, FL, USA
RE: Hydrophobic material to stop frost
RE: Hydrophobic material to stop frost
Chris DeArmitt PhD FRSC CChem
www.phantomplastics.com
Consultant to the plastics industry
RE: Hydrophobic material to stop frost
That is a novel solution. It is easy to vacuum form a film of kynar around the parts (I wonder if pvdf paint would also work). I just have to figure out how to make them shake :)
You should see if someone has tried that for deicing.
RE: Hydrophobic material to stop frost
Chris is pointing out how to make it shake - PVDF is a piezoelectric material. I.e., put an electrode on each face of the PVDF, and apply a sufficiently high voltage - and spung! goes the ice (well, that's the idea anyway).
RE: Hydrophobic material to stop frost
RE: Hydrophobic material to stop frost
Will the piezoelectric effect work if it is part of a multi layer film, with maybe PTFE or similar surface. PTFE is probably impossible to produce as co-extruded or laminated. PE would also release easy and be possible to make.
Regards
Pat
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RE: Hydrophobic material to stop frost
If it works I can justify the cost because of a performance increase. It will probably be cheaper than a heater or vacuum insulation.
RE: Hydrophobic material to stop frost
Chris DeArmitt PhD FRSC CChem
www.phantomplastics.com
Consultant to the plastics industry
RE: Hydrophobic material to stop frost
TTFN
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RE: Hydrophobic material to stop frost
Chris DeArmitt PhD FRSC CChem
www.phantomplastics.com
Consultant to the plastics industry
RE: Hydrophobic material to stop frost
sorry...
RE: Hydrophobic material to stop frost
Here are two possibilities that you may want to also look at. the Teflon based one from Elastone and the PVDF one from Saf. The Saf site contains a lot of information on PVDF coating systems.
http://www.elstonecompany.com/id59.html
h
RE: Hydrophobic material to stop frost
I think the issue is the word "slight." Most piezo materials can displace a few angstroms for thin layers, and even then, require voltages on the order of 100V.
TTFN
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RE: Hydrophobic material to stop frost
Chris DeArmitt PhD FRSC CChem
www.phantomplastics.com
Consultant to the plastics industry