Silly Putty

toys · materials science · non-Newtonian fluids · weird physics

Born from war research. Silly Putty was invented during World War II when scientists were trying to create a rubber substitute for the United States military. Instead of making rubber, they accidentally created something way more fun!

Speed changes everything. Silly Putty acts like a solid when you bounce it fast or stretch it quickly, but it flows like a liquid if you let it sit or pull it slowly. This makes it a non-Newtonian fluid, which means it doesn't follow normal liquid rules.

Bounces and stretches. You can bounce Silly Putty like a ball, stretch it like taffy, or even break it apart by pulling hard and fast. The same material can do all these different things depending on how you treat it.

Silicone polymer magic. Silly Putty contains special chemicals called viscoelastic silicones that give it its weird powers. These long chain molecules can arrange themselves to act either rigid or floppy depending on the situation.