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Q & A: plastic dielectric

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Most recent answer: 10/22/2007
Q:
Is plastic a dielectric?
- Hannah
Ventura, CA, United States
A:
There are all sorts of plastics. Some are deliberately made to have conduction electrons, ones that can move across the material when pushed by an electric field. These then are electrical conductors. More typical plastics have very few conduction electrons. These are insulating dielectrics. Teflon and polyethylene in particular make very good insulators. They do play a different electrical role than a plain vacuum would, however. They have many electrons which can slosh back and forth short distances when pushed. These increase the "dielectric constant" meaning that if you put a piece of plastic between two metal plates, the capacitance of those plates would go up. So these materials are called "dielectrics".

Mike W.

Lee H


(published on 10/22/2007)

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