which materials are good insulators?
922061
An insulator is a material containing no electrical charges. When a voltage is sent across an insulator, no charges flow, so there is no electrical voltage\n\nGenerally,all non metals materials are good insulators.Such as plastic,glass,rubber(frying pot handle)
54282
I think that the question must be -What is an electrical insulator?-, because it's material that does not have much free electrons, so the energy to make them jump out of the atom is so great that in normal situations (unless the voltage is really big, like a thunder) the electrons won't flow through it.
674634
Heat is transferred by conduction, convection and radiation. In medium-temperature applications radiation would only be a small part of the total, and an opaque material will prevent radiative escape of heat in any case. Conduction and convection are minimized by the structure of a typical insulator in addition to the material properties mentioned in the first answer. Styrofoam, for instance, consists of very thin partitions of styrene plastic which enclose gas-filled bubbles. This means each convection cell or mixing space is small and essentially a small proportion of the total insulation thickness, so you don't have the coldest internal gas mixing with the hottest gas. Conduction is low because gas conducts heat more slowly than a solid. The conduction path through the solid styrene is convoluted and of small thickness, both of which minimize conduction. In houses, fiberglass insulation uses similar principles except that the air spaces are connected. This means a larger convection cell potentially exists, but it is baffled by all the glass strands, so circulation and mixing are much slower and smaller-scale.
809561
malleable and ductile lustrous conduct heat and electricity high melting points almost all are solids at room temp except mercury
470377
A substance as germanium or silicon whose electrical conductivity is intermediate between that of a metal and an insulator.
850017
Insulators do not have free electrons to conduct heat or electricity.\n\nMetals, on the other hand, DO have free electrons, and so conduct electricity and heat.  ALL elements can be classified as either conductors, semiconductors, or insulators, depending on how easily electrons will flow.\n\nThe only exception to this rule is diamond, which is an electrical insulator (no free electrons), but an excellent heat conductor.  (The reason is that heat can be transferred by atomic vibration of the diamond crystal lattice, but electricity cannot)
998795
MgO and Al2O3 have greater ionic character than SiO2. A compound melts when the lattice breaks down and a lattice breaks down when the bonds holding it in place give way.\n\nIonic bonds are stronger than Covalent ones.\n\nThere are some amorphous forms of SiO2.\n\nYes, an insulator can conduct under such conditions.
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lots of materials' properties can be found. you can try this link..
905772
Carbon (diamond) Silicon Germanium.\nMany more with doping and compounds\n\nhttp://en.wikipedia.org/wiki/List_of_semiconductor_materials
606036
First of all, copper si very good electricity conductor so, is commonly used in electrical installations, but it's coroded in free contact with oxigen an humidity which creates oxides (something like rust on iron). These oxides (unlike the iron rust) are very compact and they are practically waterproof protecting the copper material to be oxidazed further, but is very poor electricaly conductive. Instead, the tin material makes oxides by the same process, but they are very very thin (because of greater compactity)--order of microns, or thousent part of a milimeter-- and the electrical current can pass trough.\nDfriend :)
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Zinc Oxide\n\nGood source on the properties of Zinc Oxide:\nhttp://www.chemicalland21.com/industrialchem/inorganic/ZINC%20OXIDE.htm
34806
Because the stuff they use to coat the wire is (A) an insulator (B) flexible enough to bend where the wire does (C) durable to last at least 30 or 40 years (D) impervious to water (E)able to withstand the highest voltage the insulator is designed and UL listed for (F) able to withstand the temperature that the insulator is designed and UL listed to still be operable for.
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Corn cob is mostly cellulose and air. It is the trapped air that is the primary insulator.
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Best heat transfer should occur with a good thermal conductor like copper, to carry the absorbed heat away, coated with a thin heat-conducting layer of flat black, may be an oxide of copper.
1086026
You can get an idea on counting the discs on the insulator string and multiplying by 12kV/disc.\nAgain it is only a general rule of thumb and is not accurate.\n\nSource 50 years as an Electrical Engineer
1173893
How about glass, plastic, stone, metal, ...?
964473
Silica; it's what makes glass, and ceramics have insulative properties. Other than that, it would be petroleum products such as plastics, and vinyls. Rubber comes from a plant.