Science Focus - the home of BBC Science Focus Magazine
Why does clingfilm cling? © Getty Images

Why does clingfilm cling?

Subscribe to BBC Science Focus Magazine and get 6 issues for just £9.99

Clingfilm owes its clingy nature to it's electrostatic charge, but the plastic wrap doesn't stick to all materials equally.

Asked by: Bill Henden, by email

Advertisement

Clingfilm is either made from PVC or low density polyethylene that's treated to make it stretch.

When you unroll the clingfilm, some of the electrons on the surface of one layer get pulled away onto the adjacent layer. This creates patches of positive and negative electrostatic charge. Because clingfilm is a good insulator, this charge persists for quite a while. When you wrap the clingfilm around itself or another insulator (like glass) the electrostatic charge induces an opposite charge in the other surface and the two stick together.

If you try this on a conductor, like metal, it won't stick because the charge is dispersed.

Read more:


Advertisement

Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.

Authors

luis villazon
Luis VillazonQ&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.

Advertisement
Advertisement
Advertisement

Sponsored content