We will show by designing an electric circuit that thermoplastics are poor conductors of electricity.

The things we require are:

* a bulb

* Some wires

* A battery

* A piece of metal, and

* A plastic pipe.

Set up the circuit first with the metal and then with the plastic pipe (as shown in the figure).’

After you switch on the current, you will observe that the bulb glows in the former case, in which we have connected metal. In the latter case, the bulb does not glow, in which we have connected plastic pipe. Hence, a plastic pipe (which is a thermoplastic) is shown to be a poor conductor of electricity.