Gumdrop Chains and Shrinky Necklaces
A gumdrop (molecule) chain
A cross-linked polymer model
Procedure:
- Thread a needle with strong thread.
- Thread a gumdrop and knot to hold in place.
- Continue to add gumdrops, carefully knotting and spacing about 2.5 inches apart.
- Do a second chain.
- Connect the two chains by threading the two chains together at the gumdrops. Try to leave about 2 inches between the gumdrops.
- Gummy bears can be substituted for the gum drops.
Polymers are giant molecules (too small to see) made up of smaller molecules called "monomers". By crosslinking your gumdrop chains, you have created a crosslinked polymer. They won't behave like unlinked chains: they can't move as easily.
Click here to read more about what a polymer is.
Click here to read more about crosslinking.
Thank you to Ruth Kinsler for finding this activity in Super Science Concoctions Jill Frankel Hauser, Williamson Publishing, October
1996, ISBN#1885593023
Take a look at these books that can be used with polymer activities:
- One Lonely Sea Horse, Saxton Freymann & Joost Elferrs, Arthur Levine, April 2000, ISBN#0439110149
- Gummy Bear Counting Book, Lindley Boegehold, Anness Publishing Ltd., March 1999, ISBN#0754800741
- Zack's Alligator, Shirley Mozelle, Econo-Clad Books, October 1999, ISBN#0785761055
- Tops and Bottoms, Janet Stevens, Harcourt Brace, March 1995, ISBN#0152928510
Try these activities: "Doing Science" by asking questions:
Why not do some more fun things with your gumdrop chains?
-
What happens to your chain if you tie the ends together? See what neat
mixtures of some linear chains and necklaces you can make. Draw the ones
you make and describe their properties:
- How do they move if you pull on just one point?
-
You made one crosslink between two linear chains. What happens if you make
more crosslinks between these two chains? With other chains?
Record your observations in words and drawings.
Written by Gina Watkiss, Georgia Polymer Ambassador
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