Slime has seen a resurgence in popularity since the 80s and 90s and has become the go to project for kids to do at school, in day cares, and at home. And while there are many ways to make it look cool and the kids have so much fun with it, it eventually tends to end up everywhere it’s not supposed to—clothes, the couch, the carpet—you name it, someone has probably discovered it there. And this has led to slime being banned in homes across the world. So we will explain exactly what slime is, and how to clean it up when it gets somewhere it shouldn’t.
What is Slime? Just about everyone has made some type of slime before. Remember Oobleck? That was a type of slime made from cornstarch. It flows like a liquid, but its ability to flow (called viscosity) is not the same in all situations. This is called a non-Newtonian fluid, because it does not act the same as regular fluids like water and oil. When you pour slime or just hold it in your hand, it has a low viscosity and flows like a thicker liquid, but when you squeeze it or pound it on the table, it feels hard.
The slime that is popular now is very similar to this. There are many different ways to make slime. The most popular one, and the one that tends to be the most difficult to clean up, is made up of two main ingredients, the slime base, and the slime activator. The base is polyvinyl alcohol (PVA) or something containing PVA. School glue contains PVA, and is often one of the ingredients in homemade slime recipes because it is so readily available. Some face washes and soaps also contain PVA. The slime activator contains some form of Borax. Some popular activators are Borax, liquid starch, contact lens solution, laundry detergent, saline solution, and eye drops.
To make the slime, the base containing PVA is diluted in water. Then the slime activator is added to the water. A series of reactions takes place until you have boric acid, which reacts with the water to form borate ions. Hydrogen bonds then form between the borate ions and hydroxide groups of the PVA molecule from the base, which creates cross-links that form a new polymer (slime). The new cross links are strong, and trap a lot of water, so slime is wet. You can change the consistency of slime by changing the ratio of glue to borax. The more glue you have, the less crosslinks, so you get a more fluid slime. The less glue you have, the stiffer your slime.
How to clean up slime: Now that we know what it is, we will learn how to clean it up. Adding a base to the slime will cause it to firm up. But if we add an acid to the slime, then the crosslinking gets broken, and it will produce a liquid with a lower viscosity. So, vinegar to the rescue! So if you get slime in your carpet, on clothes, on the couch, or even on the floor, follow the steps below in order to remove it:
1. Remove as much of the excess slime from the clothing as possible with your fingers.
2. Pour vinegar on the slime spot. If it is on clothing or something else that is movable, do this step over the sink or in a container to help control the mess.
3. Get a clean scrub brush and scrub the spot. The vinegar will get worked into the slime as you scrub and help dissolve it by disrupting the crosslinking bonds. Repeat steps 2 and 3 until the slime is gone.
4. Give the area a good rinse. If it is loose fabric, rinse it in in the sink, and then wash as normal in the washing machine. If it is carpet or a couch, go over the area with clean water in a carpet machine.
Now that you know what slime is and how to clean it up, you don’t have to be afraid to allow it into your home anymore!
Sources:
http://www.rsc.org/learn-chemistry/resource/res00000756/pva-polymer-slime?cmpid=CMP00006699
https://www.thoughtco.com/slime-science-how-it-works-608232
https://littlebinsforlittlehands.com/slime-activator-list/
https://www.funathomewithkids.com/2014/08/the-science-behind-slime.html?m=1
https://www.lsu.edu/science/chemistry/news/spotlight/chem_demo/Demo-3-Silly-Putty.pdf
By: Tamara Pendergrass