Polymers Are Molecules Too!
How are polymers different than small molecules?
So many ways! Polymer chemistry and polymer physics are big areas of research both in the recent past and today because connecting a bunch of small molecules into one big one results in lots of interesting changes.
To give you a metaphor, let’s talk about pasta. Start with uncooked macaroni and uncooked spaghetti: If you try to move your hand through a bowl of uncooked macaroni you won’t have much trouble, but if you had spaghetti noodles all lined up and you tried to move your hand through them (in either direction!), you’ll run into problems. You either need to break the noodles or you need to carefully thread the noodles through your fingers. Both of these actions require energy (enthalpy in the first case and entropy in the second).
Now let’s cook those noodles. Stick a fork in each of the bowls and spin it around. With macaroni, nothing happens, but the spaghetti starts to wind around your fork, gets tangled up, and so on.
Macaroni, a collection of small molecules…I mean, noodles, is totally different than polymers (spaghetti) which are also made up of flour and water, but are much longer. The raw and cooked spaghetti aren’t just easy to imagine, they’re great ways to think about polymers in different states (solids and liquids, glassy states and polymer melts).