Cracking open its egg-shaped packaging, exploring its bizarre, mushy properties, and inevitably leaving it on top of the heater and letting it melt all over the carpet, playing with Silly Putty is a rite of passage for every child.
But there's an impressive amount of history, chemistry, and trivia behind these odd, polymer nuggets -- and a few surprising facts.
It was a war-time accident.
World War II, in fact.
By 1943, thanks to the Pacific erupting in combat and chaos, U.S. rubber supplies had dramatically dwindled. Unfortunately, the military desperately needed rubber to keep the war effort humming along, so the War Production Board tasked engineer James Wright with developing a synthetic rubber to wean the country off foreign imports. Mid-experiment, Wright tried mixing boric acid with silicone oil. The result was a soft polymer that, when dropped on the floor, bounced around pleasantly. It wasn't much good for jeep tires or boots, but clearly Wright had stumbled upon something pretty cool nonetheless.
His discovery was first introduced as a toy at the International Toy Festival in 1950, and since then it's sold over 300 million eggs -- weighing, in total, somewhere around 4,500 tons.
Sometimes it's a liquid. Sometimes it's a solid. Which is it?
A little bit of both, apparently.
According to science, Silly Putty is a viscoelastic liquid, and whether it acts as a solid or a liquid depends how long you look at it. Over long enough time periods, it behaves like a liquid -- it flows from place to place, and if you leave it out it'll eventually end up as a puddle. In the short term, though, it's more like a solid: it bounces, for one thing, and if you give it a sharp blow it'll shatter into pieces. It shares its schizophrenic state-of-matter with peanut butter, automatic transmission fluid, and various kinds of paint.
[Related video: Magnetic toys send kids to hospital]
One of its most famous tricks doesn't work any more.
Everybody knows Silly Putty can lift the print from newspapers and comics, right? Actually, if you've tried it lately, you might have been disappointed in the results.
Nothing's changed with Silly Putty, but something's changed with newsprint. Specifically, newspapers have moved away from petroleum-based inks over the last couple of decades, switching to dyes based on soy products instead. The new inks are cheaper, sharper, and better, but the Silly Putty party piece doesn't work anywhere near as well on them.
It's been to space.
Well-known as an international best-seller, Silly Putty is also a success in outer space.
Aboard the Apollo 8 space mission, to be precise, which was the first manned spacecraft to escape Earth's gravity and orbit the moon. The three-man crew took a chunk along to hold down tools and to relieve boredom on the six-day voyage. Think bouncing Silly Putty around the room is fun on Earth? Try it in zero gravity. We could totally do that for six days.
You can make your own.
Commercial Silly Putty recipes are closely guarded secrets, and likely require some hardcore chemistry skills. But you can make your own version with a few common household ingredients.
The simplest of all: just mix two parts of Elmer's white glue with one part liquid starch. It won't quite have the finesse of the real thing (and you'll need to keep it in a sealed container in the fridge), but it's not a bad substitute in a pinch. You know, for those times when you absolutely have to have some Silly Putty. You have those times, right? It's not just us?