- Two common liquids are mixed, and the reaction makes a solid that has the properties of rubber. This solid is a polymer. In this lab, you will produce a solid, silicate based polymer.
MATERIALS:
Safety goggles
Plastic disposable gloves
Sodium silicate (water glass) solution, 20 mL
Ethyl alcohol, 5-10 mL
Small paper cup for each solution
Stirring stick
Paper towelsPROCEDURE:
1. Measure 20 mL of sodium silicate solution and pour it into a small paper cup.Avoid contact with your skin.
2. Place 5 mL of ethyl alcohol in another paper cup. Remember, alcohol is flammable.
3. Add the alcohol to the sodium silicate solution.
4. Using a circular motion, stir with the stick until the substance formed is solid.
5. Place the polymer in the palm of your hand and gently press with the palm of the other hand until a spherical ball that no longer crumbles is formed. Be patient. Moisten the ball occasionally by holding it in a small stream of water from the faucet.
6. Try bouncing your ball.
7. Store the ball in a small plastic bag. If it crumbles, it can be re-formed.
REACTION:
- Silicon is a very interesting type of atom. Like carbon, silicon makes four chemical bonds and can branch out in 4 directions to make long chains. In sodium silicate, the silicon atom is fonded to four oxygen atoms and is not linked in any chains. The ethyl alcohol has just two carbon atoms. When sodium silicate and ethyl alcohol are put together, the silicate particles begin to link up with each other to form long chains as the ethyl groups ( sometimes shown as “R”) replace oxygen atoms in the silicate ion. Some become cross-linked between chains. Water molecules are byproducts of the formation of the polymerization bond.
The large molecule is a solid. It is a type of silicone polymer:
R R | | O | O | O / \ | / \ | / \ / Si Si Si | | | R R R
Back to Lab Dad's Laboratory
- Silicon is a very interesting type of atom. Like carbon, silicon makes four chemical bonds and can branch out in 4 directions to make long chains. In sodium silicate, the silicon atom is fonded to four oxygen atoms and is not linked in any chains. The ethyl alcohol has just two carbon atoms. When sodium silicate and ethyl alcohol are put together, the silicate particles begin to link up with each other to form long chains as the ethyl groups ( sometimes shown as “R”) replace oxygen atoms in the silicate ion. Some become cross-linked between chains. Water molecules are byproducts of the formation of the polymerization bond.
MAKING A SOLID POLYMER
"SUPER BALL"
INTRODUCTION: