The other day, I lost a bubble gum blowing contest to my 9-year-old. Neither of us was anywhere near the world record diameter of 50.8cm that American Chad Fell set in 2004, but it got me wondering about gum.
In the old days, various people chewed various things. The ancient Mayans chewed chicle, made from the sap of the sapodilla tree. This sap was made of long, tangled molecular chains that stretched out when pulled. These natural polymers were used commercially for a while, but after World War II, chemists figured out how to use synthetic plastics and rubbers as a gum base, so they didn't have to worry about trees any more.
Bubble gum is made to be extra stretchy. Frank Fleer invented bubble gum in 1906 and called it Blibber-Blubber. Perhaps it was before its time, or maybe it was a lousy name, but apparently sales did not expand. In 1928, the Fleer Corporation had an accountant named Walter Diemer, who developed the pink Double Bubble, bubble gum, instead of counting beans.
The warmth of your mouth softens the gum. Chewing separates out the sugar and colouring and helps align the long molecules in the gum base. To blow a bubble, you're supposed to chew until all the flavour is gone, so that the smaller sugar molecules don't weaken the bubble.
Some modern gum-base ingredients can include polyethylene, the most common group of plastics, which can take on many different forms depending on its formulation. It is used in hula hoops; ketchup containers; as a rubbery synthetic polymer found in white glue, called polyvinyl acetate; and as butyl rubber, which is used in caulking and to line car tires.
Gum base does not react in your mouth or break down in your stomach, which is kind of interesting and kind of freaky. And even though Willy Wonka taught us that bad things can happen to kids who chew too much gum, if you swallow the stuff, it should still come out on schedule.