I got curious as to why plastic cling wrap sticks to itself. I mean the clear plastic stuff that people use to wrap leftover food and cover dishes. I thought it must be static electricity but I found this: Re: Hi, I really need to know the way SARAN WRAP/CLING WRAP works, thank you
Quote: "Scientists had to find some way to make PVdC and LDPE cling to itself and
discovered that certain other LOW molecular weight polymers that weren’t quite
compatable with the host would do the trick. The two most commonly used today
are polyisobutylene and poly[ethylene-vinylacetate] or PIB and EVA, for short.
Unlike magnetism, in which like poles repel each other, in adhesive chemistry
like materials attract each other. When the low molecular weight additives are
put into a high molecular weight host of different composition, they tend to
not mix [they form seperate phases]. When the film of PVdC or LDPE contacts
itself, the PIB or EVA in the one film seeks out and associates with PIB or EVA
in the second film surface. Since the additives are low in molecular weight,
they are much more mobile than the host polymer. Higher mobility leads directly
to the rapid development of an association that is perceived as ‘cling’."
The gist is that chemical affinity, not static electricity, is the answer.
Did a search of GQ and found this: http://boards.straightdope.com/sdmb/showthread.php?t=397155&highlight=plastic+wrap
So Dopers other than myself also think static electricity is the culprit.
Your comments, please.