The Velostat

Velostat is a carbon impregnated polypropylene.  The plastic itself would have a conductivity of zero.  The carbon allows for a little conductivity.  This property makes it quite handy as a shielding material.  The other attractive quality is it that is essentially plastic film.  As such, it can be used in  a myriad ways, including liners in fabric.

The actual term Velostat is the trade name  (much like Kleenex is for tissue) created by the manufacturer: 3M.  There are some current of brands coming to the market.

here are some of the numbers I stole from the interwebs:

3M™ Velostat™ 1880 Properties
Property Typical Value
Material Polypropylene
Thickness 0.125 in. (3,2 mm)
Hardness 70-75 Shore A
*Resistance
(Surface to Ground) 4 x 102 ohms
(Surface to Surface) 2 x 102 ohms
**Resistivity 102 ohms-cm
*Tested per ESD Association Standard S4.1 at 72oF, 50% RH using
3M 701 Test Kit for Static Control Surfaces (Megohmmeter)
**Tested per ASTM D 257

My physical description:  Velostat is a black plastic with one matte side, and another with a slight luster.  It is more substantial than black trash bags and does seem to have the capacity for static build up that many plastic films do.

Intended uses:

The intended use for the velostat was a semi-soft capacitor.  The labor and size for the product seems to outweigh most benefits for such use.  However, one has been made.  The velostat is used as the insulating material.  Given it’s slight ability to past current. the theory is that it will have a more favorable dielectric constant.  This will be compared to a similar but larger model made with clear cling wrap as in insulator.

If this fails, one possible imaginary use for the material would be the indoor/outdoor umbrella.  Since velostat intended as a shielding agent, and that many joke that the distributors of such products are protecting their brainwaves from aliens, it makes sense to create a fashionable alternative.  This would be an umbrella made of layers of various shielding materials and finishing with sexy black Velostat.  It would protect you from the elements outside and from EMF regardless of location.  If created large enough, one could have a portable Cone of EMF Silence (CoES - I made that up and I am trademarking it - right now.)

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