Polymers are really big molecules that are made when lots of other molecules stick together in a pattern that repeats. Fun fact: the word polymer is Greek and it means ‘many parts.’
The smaller molecules that join together are called monomers. Imagine a monomer as a paperclip… link a bunch of paperclips together in a chain and you have a polymer!
Some polymers are found in nature, like cellulose or starch. Other polymers are made in laboratories, like plastics or polyester fibers used to make clothes!
Here are some of our favorite ways to experiment with polymers!
- Zipper gallon sized plastic bag
- Sharp Pencils
- Aluminum pan or other basin to work over (just… in… case!)
- Fill plastic bag with water and zip closed
- Insert sharp pencil(s) straight through the bag!
- Don’t hesitate, just push straight through the other side.
Polymers are made up of long chains or strands of molecules, a plastic bag is made by linking those long chains together. When we stick the pointy end of the pencil through the bag, those chains stretch, but then tighten back up around the pencil sealing the bag again! Unfortunately, it doesn’t work as well in the opposite direction. Once we remove the pencils, the polymers don’t seal the hole again completely.
- Borax solution
12:1 solution – warm water to borax
- Blue or clear school glue
- Spoon or craft stick to stir the mixture
- 2 paper cups
- In a large cup labeled ‘Borax Solution’, pour 4 tablespoons warm water and 1 teaspoon borax. Stir the mixture to dissolve the borax.
This is a 12:1 ratio of water to borax powder and you’ll need enough for 1/2 teaspoon for each bouncy ball.
- Pour 1 tablespoon of glue into the other cup.
- Add 1/2 teaspoon of the borax solution you just made and 1 tablespoon of cornstarch.
Do not stir.
Allow the ingredients to interact on their own for 10-15 seconds and then stir them together to fully mix.
- Once the mixture becomes impossible to stir, take it out of the cup and start molding the ball with your hands.
- The ball will start out sticky and messy, but will solidify as you knead it.
- Once the ball is less sticky, go ahead and bounce it!
- You can store your plastic ball in a sealed zipper bag when you are finished playing with it.
NOTE: The ball will dry out in the air eventually. If it dries and no longer bounces… you can make a new one!
The bouncing ball in this activity is made from a polymer. Polymers are molecules made up of repeating chemical units. Glue contains the polymer polyvinyl acetate (PVA), which cross-links to itself when reacted with borax.
- Jello (any flavor powder)
- Cup or bowl
- Pour out a small amount of Jello powder into a bowl or cup.
- Using the spoon, drip a few drops of water into one spot of the powder.
- Notice the powder becoming connected together where the water was dripped.
- Pick up your gum drop and eat it!
The water that is added to the powdered Jello allows the protein chains in the Jello to link together forming a polymer gumdrop!