Editing Polymer Milk Jug (section)

== Demonstration ==

# Hold the container in one hand and the heat gun in the other. Turn the heat gun on and slowly wave it back and forth over one side of the container. 
# While heating the container, explain to the audience or students present that the plastic is starting to melt, and the bonds are getting weaker. Point out to them when the side of the container turns clear, and continue to heat it until the clear spot is several inches wide.
# Turn off the heat gun, and put the mouth of the container to your lips with the now-clear side facing upwards. Blow into the container gently and in a controlled fashion, and watch as the clear side expands and becomes a bubble! If you blow too quickly, the bubble will pop and be less impressive. Continue to blow into the container until the clear plastic all turns foggy again.
# After a minute, the bubble will be cool enough for students to touch and feel. It is very different from the rest of the container!
# After making the first bubble, you can make up to three more bubbles by using the other three sides of the container. Don't try to use the bottom of the container; The seam will break open once you start blowing into it.