Yael: Heads up!

Don: Whoa!

Y: Good catch.

D: Is this a superball?

Y: Yup, a Zectron ball.

D: A what? I'm sure it's a superball.

Y: That's right, a vulcanized polybutadiene ball.

D: Huh?

Y: They're all the same thing. Superballs are made of the material vulcanized      polybutadiene. When Norman Stingley synthesized this compound in 1965, he gave      it the flashy name Zectron. It's the properties of this compound that make superballs      super fun.

D: So it's this poly-whatever that makes superballs super fun?

Y: Yep. Polybutadiene molecules are essentially long chains of thousands of carbon      atoms. Like rubber bands, these chains are elastic and regain their original shape if      stretched. But when polybutadiene is heated at high pressure in the presence of      sulfur, a chemical reaction called vulcanization occurs. The reaction causes sulfur      atoms to forge connections between carbon chains creating a giant network.

D: So the sulfur atoms act as bridges?

Y: Right, and these bridges restrain the carbon strands from sliding past each other,      making the material harder and more durable. Thus, when a superball bounces, its      shape barely distorts. Tennis balls and racquetballs flex and compress a lot in      comparison. Because the sulfur bridges limit how much a superball flexes, little      energy of motion is expended to return the superball to its original shape. In fact,      about 92% of a superball's energy going into a bounce remains after the bounce.

D: So that's why superballs can bounce so many times before stopping.

Y: Exactly.

D: Think fast!

     [GLASS BREAKING]

Y: Don!  

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A Moment of Science®