Statically charging polypropylene sheets

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Statically charged polypropylene sheets, like those from Magic Whiteboard, can adhere to surfaces such as walls and paper. The method of charging these sheets is debated, with suggestions ranging from production techniques to static generation during unrolling. While they may initially hold a charge, environmental factors like moisture from walls can diminish this effect over time. The discussion highlights that similar materials, like plastic wrap, often use cling agents to enhance sticking ability. Overall, the longevity of the static charge on these sheets is limited under normal conditions.
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So recently, I discovered this: http://www.magicwhiteboard.co.uk/

It's a statically charged polypropylene sheet that sticks to walls, paper, etc. Apparently they retain their static for a long time.

How do they charge these? A giant Van de Graaff generator? Rubbing it against a large carpet? Or is the sheet charged somehow during the process of production?
 
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I don't know for sure but I suspect the static is created as you unroll it.
 
Catapult said:
So recently, I discovered this: http://www.magicwhiteboard.co.uk/

It's a statically charged polypropylene sheet that sticks to walls, paper, etc. Apparently they retain their static for a long time.

How do they charge these? A giant Van de Graaff generator? Rubbing it against a large carpet? Or is the sheet charged somehow during the process of production?

They probably haves a large supply of cats in the factory. :biggrin:
 
Those sheets may be statically charged when you first unroll them, just like many other kinds of plastic foil, but I don't think they are able to keep that charge for a long time under normal circumstances.
You can take any normal plastic foil and stick it to a wall by rubbing over it. But on most walls the foil will fall off again within a few hours. Wood and wallpaper are hygroscopic. So the moisture contained in those substances will slowly discharge the foil.
However if you "glue" plastic foil to a metal wall (or a wall covered in aluminum foil), it can stick there for years.

Anyway, in my opinion that whiteboard foil works similar to plastic wrap, which often has a cling agent added to it (e.g. polyisobutene) to increase the Van der Waals forces that make it stick.
 
DrZoidberg said:
Those sheets may be statically charged when you first unroll them, just like many other kinds of plastic foil, but I don't think they are able to keep that charge for a long time under normal circumstances.
You can take any normal plastic foil and stick it to a wall by rubbing over it. But on most walls the foil will fall off again within a few hours. Wood and wallpaper are hygroscopic. So the moisture contained in those substances will slowly discharge the foil.
However if you "glue" plastic foil to a metal wall (or a wall covered in aluminum foil), it can stick there for years.

Anyway, in my opinion that whiteboard foil works similar to plastic wrap, which often has a cling agent added to it (e.g. polyisobutene) to increase the Van der Waals forces that make it stick.
https://www.youtube.com/watch?v=S65ZzffW-Cw
Makes sense, thanks for your answer http://gizmodo.com/5807661/how-does-cling-wrap-cling
 
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