What makes clingfilm sticky?
Clingfilm is made of thin plastic, a good insulator, ensuring that it holds an electrostatic charge for a while.
When the clingfilm touches another insulating surface, such as glass, the charged clingfilm is attracted to the opposing charge of the surface.
But don’t bother trying to stick clingfilm to a conducting material such as a metal bowl – its electrostatic charge dissipates so the clingfilm quickly loses its sticking power.
Answered by Alexandra Cheung