Crazy Putty

Stretch it, shape it, squish it! Putty first became a beloved childhood toy in the 1950s. But kids from that time period would hardly recognize the versions sold today. Back then, the moldable material came in only a few drab hues. Now putties exist in every color of the rainbow—and then some.

Today, you can buy putties that are magnetic, shimmer, glow in the dark, and change color. All that variety has made putty into a hot toy again. And if you love playing with this tricked-out goop, there’s someone you should thank: Aaron Muderick. He’s the inventor behind Crazy Aaron’s Thinking Putty.

Stretch it, shape it, squish it! Putty first became a favorite childhood toy in the 1950s. But today’s putties look very different. Kids from that time period would hardly recognize them. Back then, the stretchy material came in only a few dull colors. Now putties come in every color of the rainbow—and more.

Today, you can buy putties that are magnetic. Some putties shimmer, glow in the dark, or change color. Because of that, putty is a hot toy again. If you love playing with this fancy goop, you should thank Aaron Muderick. He’s the inventor of Crazy Aaron’s Thinking Putty.

Muderick used to be a computer scientist. He liked to fiddle with toys at his desk while he worked. “I had an impressive collection,” he says. His favorite was a can of putty. But it wasn’t perfect. Besides its boring color, it tended to dry out. So Muderick decided to learn chemistry and make his own! Here’s how his hard work sparked a putty craze.

Muderick used to be a computer scientist. He liked to play with toys at his desk at work. “I had an impressive collection,” he says. His favorite was a can of putty. But it wasn’t perfect. Its color was dull, and it tended to dry out. So Muderick decided to learn chemistry and make his own! Here’s how his hard work started a putty craze.

When Muderick first started investigating how putty was made, he learned that its main ingredient was a material called silicone. Silicone is a rubberlike polymer. This substance has large molecules made up of repeating units. The chemical structure of polymers makes them lightweight, durable, and elastic, so they can be stretched and molded into nearly any shape—perfect for putty.

Unfortunately, silicone is expensive. Muderick figured out that to save on costs, companies often added other, cheaper substances to their putty recipes that made the putty dull and dry. Muderick thought he could do better, so he set off in search of new materials that were nontoxic, were relatively inexpensive, could be made in brilliant colors, and would not dry out.

Muderick started studying how putty was made. He learned that its main ingredient was a material called silicone. Silicone is a rubbery polymer. This substance has large molecules made up of repeating units. The chemical structure of polymers makes them lightweight and strong. It also makes them elastic, so they can be stretched and molded into nearly any shape. That means they’re perfect for putty.

But silicone is expensive. Muderick found that companies tried to save on costs. So they often added other, cheaper substances to their putty recipes. That made the putty dull and dry. Muderick thought he could do better. He searched for new materials that were nontoxic, were less expensive, could come in bright colors, and wouldn’t dry out.

“I had to do a lot of experimenting to get the ratios in my recipe exactly right,” says Muderick. But eventually he came up with a recipe for a putty with a lustrous sheen that would stay soft for a long time.

“I had to do a lot of experimenting to get the ratios in my recipe exactly right,” says Muderick. But over time, he developed a recipe for a putty with a shimmering shine. It would stay soft for a long time.

At Muderick’s putty factory near Philadelphia, Pennsylvania, he searches for new materials with cool properties to add to his basic putty recipe. One example is thermochromic microspheres. These microscopic spheres change color when exposed to the heat of someone’s hand. Muderick uses them to make putty that changes color when touched. He also found an iridescent material used to mark high-denomination bills to prevent the money from being counterfeited. It creates a putty that shimmers.

Muderick says a large part of his putty’s success relies on ideas thought up by other scientists. “There’s this fantasy that inventors disappear into a room and then come out months later with this amazing product,” says Muderick. “But my work stands on the shoulders of hundreds of others.”

Muderick works in his putty factory near Philadelphia, Pennsylvania. He searches for new materials with cool properties. Then he adds them to his basic putty recipe. One example is thermochromic microspheres. These microscopic balls change color when they touch the heat of someone’s hand. Muderick uses them to make putty that changes color when touched. He also found a shimmering material. It’s used to mark large bills to stop people from counterfeiting the money. It creates a putty that shimmers.

Muderick says he has other scientists to thank. Much of his putty’s success relies on their ideas. “There’s this fantasy that inventors disappear into a room and then come out months later with this amazing product,” says Muderick. “But my work stands on the shoulders of hundreds of others.”