Polymer Lesson Plans
Try these hands on lessons dealing with polymers to get students thinking chemistry and the structure of molecules.
By Jennifer Sinsel
What do contact lenses, milk jugs, computers, sandwich bags, and chewing gum all have in common? They are all made out of synthetic polymers, which were originally developed by a team of American researchers led by chemist Wallace Carothers in the early 1930s. Before that time, almost everything people used was made of materials that had been around since ancient times: wood, metal, and plant and animal fibers. However, with the development of synthetic polymers came plastics, which revolutionized the civilized world – creating most of the modern items we use today!
Polymers consist of flexible, stretchable chains of molecules that repeat over and over. To get an idea of how polymers behave, you’ll need some spaghetti. Cook one batch with a few drops of oil to keep the noodles from sticking together. Try slowly stretching them, and then pull them quickly so they break. Do you see how the noodles will stretch when slowly pulled and break when pulled abruptly? Polymers behave in much the same way.
Sometimes polymer chains can get tangled up. This causes the chains to connect in more than one place, producing a stronger and more elastic polymer. Try cooking a batch of spaghetti without stirring or adding oil. After draining the water and waiting about five minutes, pull the tangled mass of noodles from the pan and try stretching slowly, then abruptly. Did you notice any differences from the single noodles?
To try making your own polymer, obtain some cornstarch, water, and food coloring. Pour one cup of water into a container (a pie tin or plastic food container works well) and add a few drops of food coloring. Finally, add two cups of cornstarch a little at a time, kneading slowly with your hands. The substance will become thick and hard to mix, but keep at it. When you’re finished, you should have created some ooze - a polymer. You can have your students investigate this polymer, which has the properties of both a liquid and a solid. What happens when they rub a finger across the top of the ooze quickly? When a hand is rested on the top of the ooze? When it’s squeezed? Is it elastic? Is it flexible? Is it affected by temperature? Do different objects float or sink? Endless opportunities for inquiry investigations exist. For more ways to learn about polymers, try the following lesson plans.
Polymer Lesson Plans:
Students examine and determine properties of polymers. They explore basic concepts of polymer chemistry and work in groups to produce a polymer, slime. In addition, they list examples of every day polymers and their benefits.
Students explore the different types of polymers while participating in a hands-on activity. The students, themselves, will be the different atoms and molecules involved in making a polymer to help them learn about the structure of these unique molecules.
Students examine how plastics have been integrated into everyday products. In groups, they identify products without plastics and try to redesign a product using fifty percent less plastic.
