Polymer Lab Group Investigation

Before beginning our lab, I felt that the corrosiveness of the acetone and ethanol would be much more effective at breaking down the polymer. However, the story was far to the contrary. I believe my hypothesis was not supported by the findings of our lab.

(change in size of the polymer)

The lemon juice, with its pH of 2.7, quickly dissolved the polymer's links, while the acetone and ethanol did very little. Lemon juice's acidity seemed to quickly and effectively unhook the polymer. You could even see small little polymers, of a few monomers that remained together. As a consequence, the whole beaker fogged up. However, I think that the acetone and ethanol would have more gradually dissolved the bonds, due to any corrosive's prolonged weathering process. The immediate effects of the acetone and ethanol were small due to their neutral pH. When the polymer broke down, it had a very slimy and floppy texture. When compared to the stagnant control test, the lemon juice-dissolved polymer was roughly 90% smaller in mass.

The polymer before depolymerization

The depolymerized product

The acetone weathered polymerThe milky lemon juice beaker

During our experiment, we changed what we were going to do. Instead of making a double batch of borax and water, we realized that we could just use the 25 mL of borax and water twice out of the same glass. Also, we thought that stirring the polymer with the desired corrosive would excite depolymerization. However, there was no change due to the stirring.

I believe that our choice of acetone and ethanol were redundant, due to the similar properties in corrosion. Instead, I would like to test an extreme base, like bleach, which has a pH of 14. I am very surprised though that acetone didn't quickly dissolve the polymer into monomers, especially because of the big label that says "Do not use near plastics." Also, it is used as nail polish remover because of its ability to corrode substances, like nail polish.

Overall, I feel our experiment was successful in the manner that it gave extremely conclusive results, finely showing that lemon juice was the most effective way to break a polymer into monomers.