Making Slime was all the rage in 2017 and plenty of people are still doing it. Slime is fairly simple enough that even grade schoolers can do it, yet still intriguing enough to keep high school kids interested. It is simply too much fun to play with.
There are quite a few ways to make Slime. In this post I will show you a few recipes and variations you can try. In a nutshell, chemistry of making slime is as follows: you take a long chain polymer such as polyvinyl alcohol or polyvinyl acetate (white glue) and separate the molecules by dissolving them in water. Then, by introducing borax, you rejoin the polymers to form a more solid co-polymer network. This new configuration of polymers is that gooey substance commonly called slime.
Some of the ingredients commonly used to make Slime include: white glue, food coloring, water, polyvinyl alcohol, shaving cream, clear glue, borax, etc.
Caution:
Slime is fun to play with, but take care in handling and storing it. In particular, be aware that slime can be absorbed into fabric and thus can potentially ruin or damage clothing, furniture or carpets. Slime should never be left lying around on or near absorbent fabric, carpet or similar materials. Do not let children or pets eat slime. When not in use, slime can be safely stored in airtight plastic containers or ziplock bags and kept in the refrigerator.
Recipe 1: Slime made with white glue
Ingredients: Elmer’s Glue (or other white glue), food coloring, water, Borax, large bowl, cup or bowl.
Method: In a large mixing bowl make a Borax bath soilution by adding 2-3 tablespoons of Borax to 1-2 quarts of water. The measurement of Borax does not have to be precise. But remember, the more Borax you use, the thicker or more solid your slime will come out. As you try to make the slime in this bath, if the slime feels to loose and slimy, you can add more Borax to firm it up. But we’ll get to that later.
Next add a measure portion of water to a separate large cup or bowl. To this add the same portion of white glue. for example if you had 6 oz of water, then you would add 6 oz. of glue to it. Stir until the two are completely mixed. Add food coloring of your choice. It doesn’t take much. Start by adding a few drops at a time until you get the color you want.
Take your colored glue solution and slowly pour it into the bath while stirring. Swirl it around in the bowl and it will start start to congeal and become slimy. You will need to remove it from the water and hold it in your hand. This may be difficult at first because the slime will be so loose. The way to make it more solid is to pass the slime from hand to hand. As you do this, the water will start to absorb into it and it will solidify more. If this doesn’t work, you may try putting more Borax in the borax bath a re-bathing the slime.
UPDATE: Because of the popularity of making slime, a clear glue product has recently appeared on the market for people who want to make clear slime. Follow the same instructions as for the white glue slime.
Recipe #2: Magnetic slime
Making your slime magnetic brings a whole new dimension of interest to this already interesting substance. The recipe for magnetic slime is basically the same as the recipe above for slime made with white glue. Since you will need to add a metal powder to make it magnetic, the slime will turn out black. Therefore, you will not use food dye to color it.
What kind of metal powder do you use and where do you buy that? The only metals that stick to magnets are iron and steel. You can purchase an iron powder or an iron/steel powder. However, these powders will start to rust after a day or two and turn your slime brown. So the best option is to use Magnetite (also known as Black Iron Oxide powder). This substance is dark black and is naturally magnetic. And unlike iron powder will not rust.
There are two ways to incorporate Magnetite into your slime. You can add it to the glue solution and mix it in before you put the glue into the Borax bath. Or, my preferred method is to make the slime first and then gradually knead the magnetite into the slime.
Now, to demonstrate your slime’s magnetic property. Your slime’s magnetic strength will not be that great. Therefore, to demonstrate the magnetic property, it will be best to use the strongest magnet possible. If you use an ordinary ceramic magnet the result will not be very impressive. Therefore, I recommend using a Neodymium magnet. Neodymium magnets are the most powerful magnets available. They come in different strengths and different sizes. The most powerful strength grade is called N48. You can use an N48 magnet or a slightly weaker one with N35 strength. For best results, buy a magnet that is a minimum of a half an inch in size, either cylinder or cube shaped. With a magnet of this size and strength, you will be able to see the your slime gradually move and stretch to reach the magnet.
Recipe#3 Clear Slime
White glue makes a good slime but people frequently complain that it is opaque. With the right material on hand, it is possible to make a clear slime, just like the stuff you see in the stores.
The method for making clear slime is similar to the method for making slime with white glue. The chemical name for white glue is polyvinyl acetate. To make clear slime, we will use a chemically similar material, polyvinyl alcohol. Polyvinyl alcohol (PVOH) is sold in a dry form. It looks like very small granules or pellets of plastic.
To use PVOH in the recipe, you must first dissolve it in water. When you have a polyvinyl alcohol-water solution, you proceed in the same way as required for making slime with white glue. You can add food coloring to get a colored, yet clear, slime.
This slime is a little more difficult to make than white glue slime. The characteristics of the slime you make will vary depending on the concentration of your PVOH-water solution and on how much borax is in your borax bath. Gels used for medical applications are made by essentially the same process. Results will also vary depending on what grade of PVOH you use. For this project, I recommend PVOH 49-88. This material is easier to dissolve and has greater viscosity than other types.
NOTE on dissolving PVOH: this substance dissolves in hot water and requires constant stirring. If leave your mixture on a heat source, it is likely you will overheat it and burn it. If the material is overheated, it can take on a yellowish tint.
I recommend using a 4% solution of PVOH. This would be 40 grams of PVOH in 960 grams of distilled water. To make this solution, you have keep the water warm or hot over low heat while gradually adding the PVOH and stirring. This should be done slowly and will take at least 15 minutes.
You will also make a 4% solution with the Borax, by adding 4 grams of borax to 96 grams of distilled water.
Next you will combine the 2 solutions. You must use a glass or ceramic bowl for this. It is recommended that you mix 5 parts PVOH solution to 1 part borax solution. Hoewever, you can be flexible with this. Adjust the proportions to get the consistency you want. Keep in a sealed container and it will last for a long time.
Recipe 4: Slime made with shaving cream
Interesting additives for making Slime variations
To make your Slime more interesting and colorful, you can add micas or glitters. To make slime with strange textures that may sound crunchy, you can add beads, floam, bb’s or sequins.
Contact Solution
If you watch Youtube videos about Slime, you will probably come across some videos that show people making Slime using contact solution as the activator. This will indeed work, but I would like to tell you why this is a completely unnecessary waste of money. As you know, Slime is usually made with Borax which is a naturally occurring mineral. Borax is inexpensive because it is a raw mineral. In contrast, Boric Acid is a refined chemical that is derived from Borax after several stages of processing. Contact lens solution is a solution that contains a small amount of Boric acid. Boric acid will make long chain polymers rejoin the way Borax does, only it will cost you a lot more money. So, trust me, Borax will do the job of making Slime just as well as contact solution, if not better.
Materials mentioned on this page are available for purchase. Click on the any of the materials to be directed to a supplier: Borax, Magnetite, Neodymium magnets, polyvinyl alcohol (PVOH)