This lesson is an introduction to chemistry. Specifically, the exciting world of polymers! Students will learn what a polymer is, and how chemists design materials to do a variety of jobs. Students will review scientific terms including atoms, states of matter, monomer, and polymer, and discuss how the properties of objects and materials can change. Students will be given chemicals to make a polymer and see demonstrations of how the same material can do a variety of amazing jobs. (Appropriate for grades 1-4).
Lesson time: 45-60 minutes
Adult Demonstration 1: Paperclips are used to illustrate the idea of a polymer being built from monomer units.
Student Activity 1: The previous demonstration is reinforced by having the students “build a polymer” using beads and a pipe cleaner.
Student Activity 2: Students make their own polymer slime using PVA and borax solutions. The concept of crosslinking is illustrated to explain the phenomena/phase change they are observing.
Adult Demonstration 2: Chemists design polymers to do specific jobs. Polymers are incredibly diverse! One example is a diaper! There are many polymeric materials in a diaper, each serving a different function. Students are often surprised to hear that a very small amount of powder is doing all the work of absorbing the liquids! A deconstructed diaper is sent for students to see. The students are then WOWed to see a small sample of powder (sodium polyacrylate) absorb a large volume of water instantly (materials provided)!
Adult Demonstration 3: To continue the theme of polymer diversity and the designed function of polymers, students are shown polystyrene in three different forms. Preparation by the chemist and its effect on the resulting product is discussed as the materials are passed around. Students then observe how a polystyrene packing peanut “disappears” in acetone.
1.PS.1: Properties of objects and materials can change
3.PS.1: All objects and substances in the natural world are composed of matter. Matter takes up space and has mass.
3.PS.3: Matter exists in different states, each of which has different properties.