Teflon Tape Secret Message

How Does It Work

Teflon Tape is a type of polymer called polytetrafluoroethylene (PTFE). That’s a really long word for a kind of polymer that has long chains of molecules lined up side-by-side and on top of each other.  If you try to stretch the tape end to end before stretching it from top to bottom, you won’t be able to stretch it much at all. That is because the polymers are bonded to each other very tightly. But, there are lots of chains stacked on top of each other. These stacks make it possible to pull the tape from top to bottom and stretch your secret message. When the polymer chains are pulled from top to bottom they slide over one another and reduce the number of chains in a section without breaking the chains themselves. When the tape is pulled back end to end, the chains are realigned and your message is legible again.

Take It Further

Try writing a message on a plastic grocery bag. Now pull the bag from top to bottom, just like the tape. Does your message “disappear?” Pull the bag back from end to end. Can you read the message again? Now try to rip the grocery bag. Does the direction of the pull make a difference in the outcome?

Science Fair Connection

Creating a secret message is pretty cool, but it isn’t a science fair project. You can create a science fair project by identifying a variable, or something that changes, in this experiment. Let’s take a look at some of the variable options that might work:

• Compare what happens when you use Sharpie® markers to write your secret message with other type of permanent markers.
• Compare what happens when you use a permanent marker to write the message and a non-permanent marker to write the message.

That’s just one idea, but you aren’t limited to that! Try coming up with different ideas of variables and give them a try. Remember, you can only change one thing at a time.