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Re: Unusual capacitor dielectrics

Tesla List wrote:
> 
> Original Poster: Steven Ivy <adder_black_the-at-yahoo-dot-com>
> 
> Thanks for the info Bert.
> I guess that must be part of the story I heard about, not megajoules,
> but big never the less. Shame their cap didn't work out. I have
> sources that indicate that work in that area is still on going and
> funny thing about reports like the one you sited it seems like the
> negative results reports always seem to somehow get released to the
> public but good results just get a new classification as secret and we
> never get to hear anything about them : (
> 
> Per your posted info and the concensus of the group water as a
> dielectric is far too fragile to use in a home built capacitor and ice
> is just not worth the trouble.
> 
> The one complaint I have about that chart you posted is that they it
> compare ultrapure H2O to common ionized water ice I am not sure if it
> would make that much difference but I suspect that de-gassing and
> de-ionization may be just as important to ice as it is for liquid H2O.
> The advantage of ice being that once crystalized water would not be
> nearly as subject to gas or ionization damage.
> 
> Since you seem to have access to some fairly obscure data I was
> wondering if there are any other liquids, preferably non-polar
> liquids, that have dielectric constants better than or equal to good
> plastics? It seems like immersing a bunch of parallel plates into a
> decent liquid dielectric would be a pretty easy way to make a
> capacitor. I have heard of people placing a common aircore variable RF
> capacitor in oil to make high voltage variable capacitor but they
> failed to mention what effect the oil had on the value of the
> capacitance I would think that the value would most likely go up quite
> a bit. How about wax potting not just as the final step but as a way
> to introduce a dielectric?
>

Oil has dielectric constant of 2-3, so that air insulated cap would wind
up being twice the capacitance.  As for other liquids that have higher
epsilon: castor oil, askarels (PCB's). 

I have some data tabulated on:
http://home.earthlink-dot-net/~jimlux/hv/insulliq.htm
 
>
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Jim Lux                               Jet Propulsion Laboratory
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