How do I measure dielectric constant? 1

[Naveen93]

Sorry if this is a stupid question that I should just research on my own, but I have a limited electrical engineering background so I figured one of you might be able to help me a bit more efficiently.

I'm not entirely sure what the purpose of this is since my supervisor hasn't explained it, but I've been tasked with finding the dielectric constant of a thin piece of plastic (think of like a piece of saran wrap that is about the size of a piece of paper). I need to be able to find this dielectric constant in order to verify that it is lower than water (we are aiming for something between 2-4, but can possibly accept something with dielectric constant between 1-20). If measuring dielectric constant is too difficult, I just need to take some sort of measurement to verify that the impedance of this material is lower than water.

I don't even really know what some of these terms mean ... I'd appreciate whatever help anyone can offer.

 

[ScottyUK]

It's a classic high school physics experiment to build a flat plate capacitor using a pair of conductive electrodes of known area and the plates interleaved with various insulators and differing thicknesses of the same insulator. Google [blue]flat plate capacitor dielectric constant measurement experiment[/blue] for some ideas how to do it, or buy/borrow any half-decent high school physics text book for a more step-by-step description.

 

[Comcokid]

Dielectric constant of water is around 80. Most solid plastics are around 2 to 12. Note I said solid as foamed plastics like Styrofoam are mostly air and have a dielectric constant only slightly more than air.

 

[IRstuff]

There's a table of dielectric constants in Wikipedia that you can use for reference:

https://en.wikipedia.org/wiki/Relative_permittivity#Terminology

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