So when most of us think of super glue, we usually don’t consider it to live in the same family as fart putty. While they do have two very different uses in the world, what you may not have realized about these two curious substances is that they share a lot of chemical properties with one another.
One of the most important characteristics that these products share is the presence of a type of chemical chain called polymers. A polymer is a chemical compound that is made up of a large chain of identical molecules all bonded together. These chains can cause for the compound to have elastic and adhesive properties. Two substances that exemplify these two properties in particular are silly putty and super glue.
Silly putty contains a type of polymer group called a silicon, which is not the same as the element silicon. These polymer chains are made up of Si-O-Si molecules and are very long and can therefore stretch and intermingle with each other in a giant mass. While these polymer chains do bend quite a bit on their own, their flexibility is also enhanced through the presence of boric acid in the putty. The boric acid binds to the OH ends of the polymer chains, creating crosslink bonds in between the chains. These bonds can be slowly broken and reformed, causing the putty to flow like a liquid when it is allowed to move slowly. As you probably already know, if you try to pull apart a ball of silly putty quickly, it will tear as if it was a solid. This is because these crosslinks are being pulled apart but are not given enough time to reform, causing the polymer chains in the putty to break away from each other. While putty does seem to be rather useful when a filler or soft, tacky substance is necessary, they aren’t always the best solution whenever an adhesive substance is needed.
Another surprisingly similar substance that actually has rather different properties than putty is super glue. While this substance is also made up of polymers like putty, it is not the ideal stress reliever to squeeze between your fingers when you’re angry. This is because super glue has extremely adhesive properties, and odds are you’re gonna have your fingers stuck together for a very long time after playing with it. Like putty, super glue is made of polymer chains, but a different type. These chains are made up of cyanoacrylates, which are cyanide based compounds that also happen to react rapidly with water. Like the crosslinks found in putty, these bonds between the polymer chains and water are hydrogen bonds. The difference is that they form much faster, but the bonds are more brittle than those found within silly putty so they don’t stretch as much.
The way that these polymers stick together and to other surfaces can differ and have a lot to do with the different factors that contribute to the Van der Waals forces within the molecules. The different types of polymers have different types of dipole interactions as well as entirely different elements involved, all of which contribute varying levels of electronegativity. All of these factors can contribute to different amounts of strength between the bonds, and therefore different levels of adhesiveness in our every day polymer based substances.
These different levels of adhesiveness can be manipulated through the combination of different types of polymers, or even the addition of different substances to the mix. While super adhesive things such as super glue can be useful for sticking objects together, there are disadvantages caused by the brittleness of these bonds. Things stuck together with super glue are stuck tight, but if there is enough twisting or a drastic temperature change, they will be more likely to shatter. This problem has been counteracted by adding rubber particles to super glue to make more stable products, such as gorilla glue. While putty technically has the ability to shatter as well, it is much less likely to do so. Putty is used generally when filling a crack or opening, rather than just holding things tight together. It can also be put to use in therapy clinics for people who are stressed, since it is malleable and won’t glue your fingers together like gorilla glue. Putty is also used while repairing ships and satellites in space as well as to hold tools in place due to its easily manipulated and mildly adhesive characteristics.
So depending on what type of job you’ve got on your hands, whether it be securing your drill to the side of a spaceship while floating in space, or sticking a picture frame in the living room back together, both putty and super glue can be very useful substances in our world. It all just depends on what type of polymers and intermolecular bonds you’re looking for!