When Justin Burton visited Spain in 2013, he saw street performers making bubbles as big as cars. Burton, a physicist from Emory University in Georgia, thought the secret to creating colossal bubbles must lie in their soapy solution.
Burton tested various bubble mixture recipes. He knew that polymers—long molecules of repeating units—help make big bubbles. Polymer chains act like a scaffold to support the walls of a bubble, explains Burton.
He believes that the street performers probably used guar seeds in their bubble mix. When you soak these seeds in liquid, they release long chains of polymers. That allows the thin soapy film to stretch farther before finally going POP!