Slime

Slime is a moist, stretchy, cross-linked polymer that you can make from white glue and household borax. The word polymer comes from the Greek words poly: many and meros: parts. Polymers are composed of many individual units called monomers. These monomers are linked together with chemical bonds to form long chains. A typical polymer is made of 1,000 to 10,000 monomers linked together.

Examples of natural polymers include wool, cotton, wood (cellulose), silk, protein, starch and rubber. Some synthetic or man-made polymers include plastics, synthetic rubber, nylon, Styrofoam, polyester, Teflon and fiberglass. It is a good idea to recycle manmade polymers to conserve our oil resources and to protect our environment. Most plastics are now recyclable. In recycling some polymers are burned, others are heated and reformed into new objects like plastic lumber, floor mats and drinking cups, others are degraded to fuels and burned to make electricity or steam.

Every day, chemical engineers are developing new polymers and finding uses for existing polymers.
The Human Polymer Chain
Four or five students stood in a line. Each of us represented a monomer. Then we linked arms. Each link represented a chemical bond. The chain we formed has many units and represented a polymer. Our chain was really flexible.

Human Polymer Chain

When some of us held onto 2 chains at once we cross-linked the human polymer chains. Now the movement of one chain depended on the movement of the others. The cross-linked chain was not as free to move around as the single chains were.

Cross-Linked Human Polymer Chain

You will need…

Making slime in plastic cups

• Plastic cups/bowls for mixing in.
• White Glue
• Borax
• Stirring spoons for mixing.
• Food coloring (optional)
• Zip Lock bags for storage

Instructions
Caution: Do not eat your polymer.

1. Take the white glue, which is a water-soluble polymer (polyvinyl acetate)
2. Mix with borax, the cross-linker
3. Stir really hard until the glue forms a rubbery material
4. Add food coloring to make it more colorful
5. Now you have a polymer to play with! Stretch it, bounce it, watch it flow
6. When you are doing playing, wash your hands

More Tips

• You can store your polymer in a ziplock bag to play with later, but throw it away after several days or it will start to mold.
• Be sure to keep it away from younger siblings who might eat it.
• Keep it away from carpet and wood furniture – it can be washed off with soap and water, but cleanup work takes away from playtime.

Did you like this activity?

If you want to work with polymers, finding new uses for them and maybe even inventing your own, you should be a chemical engineer. Click here to learn more…