What is a material that does not conduct well?

Answer 1

insulator

Answer 2

They are called insulators, more specifically thermal insulators.

Examples are rubber and glass.

Air is one of the best insulators there is (the trick is to get it to not move). Silicon is an excellent insulator.

Answer 3

There are no metals that fail to conduct heat well. By the definition of being a metal, there has to be low resistance to the movement of electrons. Because free-moving electrons are able to transfer heat through the metal, good heat conduction is a consequence of good electrical conductivity.

Note, though, that the converse is not necessarily true - just because a material has good heat conductivity, it does not necessarily mean that it will have good electrical conductivity. This is because heat transfer may also take place through atomic vibrations, which do not contribute to electrical conduction. An example is diamond, which is an insulator, but displays heat conduction that is better than most materials.

While all conduct heat well, Manganese and Bismuth are some of the worst metal thermal conductors with 7.81 and 7.97 W·m−1·K−1, respectively. Tellurium has a thermal conductivity of 1.97-3.38 W·m−1·K−1 as a metaloid.

Answer 4

Metals conduct heat and electricity well, in fact that is one of the main defining features of a metal. So in short, no, they do not not conduct heat well, they DO conduct heat well.