Modified PETRETEC
Introduction to Polymer
Chemistry
Bouncy Ball
Label one cup 'Borax Solution' and the other cup 'Ball Mixture'.
Pour 10mL warm water and 2g borax powder into the cup labeled 'Borax
Solution'. Stir the mixture to dissolve the borax. Add food coloring, if desired.
 Pour 4g of glue into the cup labeled 'Ball Mixture'. Add 4mL of the borax
solution you just made and 3g of cornstarch. Do not stir. Allow the
ingredients to interact on their own for 10-15 seconds and then stir them
together to fully mix. Once the mixture becomes impossible to stir, take it
out of the cup and start molding the ball with your hands.
 The ball will start out sticky and messy, but will solidify as you knead it.
 Once the ball is less sticky, go ahead and bounce it!
 You can store your plastic ball in a sealed Ziploc bag when you are finished
playing with it.
 Wash your work area, utensils, and hands when you have completed this
activity.


1.
2.
3.
4.
PET
Draw the Lewis Structure of terephthalic acid (HO2C(C6H4)CO2H
Use the model kit provided. Build terephthalic acid.
Does this molecule obey the octet rule, why or why not?
The other unit that is part of PET is ethylene glycol, or 1,2ethandiol. Draw the Lewis Structure of HOCH2CH2OH.
5.
Build ethylene glycol with your model.
6.
Combine the two molecules that you made in step 2 and 5 by a
dehydration reaction, removal of a water molecule. We will refer to
this molecule as the monomer unit.
7.
Draw the Lewis structure of the molecule that you have build in
Step 6.
Wait for your instructor to give you the rest of instruction.
Structures
O
OH
O
HO
O
O
OH
OH
HO
HO
O