Speaker 1: Welcome to brain Stuff production of iHeart Radio. Hey brain Stuff,
Speaker 1: I'm Lauren Vogelbaum, and this is another classic episode from
Speaker 1: our previous host, Christian Sager. For me, one of the
Speaker 1: weirdly comforting things about science is that it always leaves
Speaker 1: itself open to further questioning and exploration. You can almost
Speaker 1: always dig deeper. And that's the case with today's question,
Speaker 1: why do balloons stick to our hair? Hey, brain Stuff?
Speaker 1: Is Christian Sager here. When you were a kid, did
Speaker 1: you ever rub a balloon really fast against your hair
Speaker 1: to make it stick? What about as an adult? Well,
Speaker 1: after many years of speculation, Case Western Reserve University scientists
Speaker 1: have pinpointed exactly why this party trick happens. We've known
Speaker 1: forever that when two objects are rubbed against each other
Speaker 1: there's a build up of an electrical charge called static
Speaker 1: electricity or tribo electric charging. If the two objects have
Speaker 1: opposite charges positive and negative, they'll stick together. But some
Speaker 1: objects appear to charge more or stick more closely together
Speaker 1: than others, like the balloon on your hair. Now, why
Speaker 1: is that? According to a new study published in the
Speaker 1: journal Physical Review Materials, the crux of the phenomenon lies
Speaker 1: and how strained the balloon material is. For the purpose
Speaker 1: of this study, the scientists stretched a film of polytetrafluoroethylene.
Speaker 1: Let's just call it PTFE for now. That's one of
Speaker 1: the brand names for Teflon. They took that and they
Speaker 1: rubbed it against a film of unstrained unstretched ptf E,
Speaker 1: and they found that even though the materials were chemically identical,
Speaker 1: they generated charge transfer in one direction as if they
Speaker 1: had two different chemical compositions. The stretched or strange sheet
Speaker 1: carried the positive charge, while the unstranged sheet carried a
Speaker 1: negative charge. The more strained the material was, the more
Speaker 1: likely it was to experience systematic charge transfer. This is
Speaker 1: because the micro structure of the material was altered when strained,
Speaker 1: leading to tiny holes and cracks. These imperfections allowed the
Speaker 1: rubbing induced friction to facilitate charge transfer, leading to static electricity.
Speaker 1: In a press release, co authored Dan Lax explained that
Speaker 1: they think the void regions and the fibrils these are
Speaker 1: tiny cell fibers. They think that those were strained when
Speaker 1: the polymer had different bonding and thus a charge that
Speaker 1: was different. The researchers also examined the phenomenon using packing
Speaker 1: peanuts which just love to stick to people's arms. In fact,
Speaker 1: polystyrene peanuts and plastic bags are currently being closely examined
Speaker 1: to give us a better understanding of static electricity. Ideally,
Speaker 1: scientists will nail it down so precisely that they will
Speaker 1: be able to control it, helping to prevent tribe electric
Speaker 1: explosions such as explosions of cold dust in minds, and
Speaker 1: develop more effective products, for example, pesticides that will stick
Speaker 1: better to plants or paints that will stick better to cars.
Speaker 1: It may not seem that dangerous, but in fact static
Speaker 1: electricity can ignite fuel vapors at the gas pump, causing fire.
Speaker 1: To avoid such a catastrophe, try not to get back
Speaker 1: in the car after you start the fueling process, because
Speaker 1: sliding across the seat generates static electricity. If you must
Speaker 1: re enter your vehicle, be sure to ground yourself first
Speaker 1: when you get back out by touching the metal part
Speaker 1: of your car door. Today's episode was written by Lee A.
Speaker 1: Hooint and produced by Dylan Fagan and Tyler Clang. For
Speaker 1: more on this and lots of other topics, visit how
Speaker 1: stuff works dot com. Brain Stuff is production of iHeart
Speaker 1: Radio or more podcasts in my heart Radio, visit the
Speaker 1: iHeart Radio app, Apple podcasts, or wherever you listen to
Speaker 1: your favorite shows. H