Name

Period

Date

Silly Putty Lab

OBJECTIVE

• The borax acts as a crosslinking agent or "connector" for the glue's polyvinyl acetate molecules.

INFO

• In the case of the glue polymer, the vinyl molecules are not hooked together in long chains. They are cross-linked, or bonded along the sides of the molecules. It is borate ions which are responsible for the cross-linking. Borate ions are provided by the borax (sodium borate).

MATERIALS

• 4 oz white glue
• distilled water
• 4% borax solution (1 TBS borax to 1 cup water)
• baggie

PROCEDURE

1. Make a 50% water 50% white glue solution.
1. remove glue top & pour into baggie
2. fill bottle with distilled water
3. cover top and shake
4. pour into baggie
2. Add 1/2 cup of borax solution to baggie.
3. Seal bag and knead the mixture.
4. Squeeze out excess water over sink.
5. Observe behavior of putty.
6. Please keep off of floor.
7. Clean up.
1. pour left over solution down drain

i. BUT NO SILLY PUTTY IN SINKS!

2. throw baggies away

Additional Info

• Take a cup of water and add to it 1 TBS of borax (approx 4% solution). Stir until completely dissolved.

• The mixture of Elmer's Glue with Borax and water produces a putty-like material called a polymer. In simplest terms, a polymer is a long chain of molecules. You can use the example of cooking spaghetti to better understand why this polymer behaves in the way it does. When a pile of freshly cooked spaghetti comes out of the hot water and into the bowl, the strands flow like a liquid from the pan to the bowl. This is because the spaghetti strands are slippery and slide over one another. After awhile, the water drains off of the pasta, the strands start to stick together. The spaghetti takes on a rubbery texture. Wait a little while longer for all of the water to evaporate, and the pile of spaghetti turns into a solid mass -- drop it on the floor and watch it bounce. Many natural and synthetic polymers behave in a similar manner.
• Polymers are made out of long strands of molecules like spaghetti. If the long molecules slide past each other easily, then the substance acts like a liquid because the molecules flow. If the molecules stick together at a few places along the strand, then the substance behaves like a rubbery solid called an elastomer. Borax is the compound that is responsible for hooking the glue's molecules together to form the putty-like material.