Polymers/Purcell/Block I

Polymers

Problem: Find the change in physical properties of a polymer as a result of cross-linking.

Hypothesis: The changes in the property of the polymer will be determined by the size of the polymer.

Materials: 

500 mL Water

25 mL Elmer's glue

1 tsp. Borax

1 graduated cylinder

1 600 mL Beaker

1 250 mL Beaker

Stirring rod

Procedures:

      Put 100 mL of water into the 600 mL beaker. Next put three teaspoons of Borax into the water and stir. Then pour 25 mL of glue into the 250 mL beaker. Add the Borax solution to the glue and stir.

Once the solution becomes more of a solid, take the solid out. Pour the extra liquid down the drain. Roll the solid into a spherical shape. Next, perform a series of tests. First, describe the polymer(texture, smell). Next, rate the sliminess on a scale of one to five. Then, see what happens when a finger is slowly poking the polymer. Then try it doing it quickly. Next, slowly pull apart the putty. then try doing it quickly. Next, lay the putty down on the table. See how long it takes for the putty to stop flattening. Finally, hold a ruler vertically. Drop the ball of putty onto the table. Record the height of the first bounce.

Add the Borax solution to the glue and stir.         Once the solution becomes more of a solid, take the solid out.



Results:
      On the first test, it was found that the putty was squishy and odorless. The slime rating was two. On the slow poke test, the finger goes in will a little force. The finger does not go in quickly. The slow pull test results in expanding and pulling apart. The putty comes apart easily in the quick pull test. The blob test resulted in 2:06. The bounce test resulted in a fifteen centimeter bounce. The monomers in the glue and the Borax came together to form a polymer.
Conclusion:
     My hypothesis was partly accepted. The Description Test does not rely on the size of the polymer. The Slime Rating does not rely on the size of the polymer. The Slow and Quick Poke Tests did not rely on the size of the polymer. The Slow and Quick Pull Tests partly relied on the size of the polymer. The Blob Test highly relied on the size of the polymer. This is because the time would have been greater if the size of the polymer was greater. Also, the time would have been less if the size of the polymer was less. The Bounce test mostly relied on the spherical nature of the polymer. However, the bounce is measured from the top of the polymer at the highest point. If the putty was smaller, the top of it would not have been as great.