DIY Glow-In-The-Dark Slime

  • By Anna Rothschild
  • Posted 12.17.15
  • NOVA

What makes things glow in the dark? Find out while making your own slime with common household items in this episode of Gross Science.

Running Time: 02:54


DIY Glow-In-The-Dark Slime

Posted: December 17, 2015

Hey everyone! Today on Gross Science we’re making glow-in-the-dark slime with common household items! Woooo!

Ok, to make glow-in-the-dark slime you’ll need hot water, borax, which you can find in the laundry aisle at the grocery store, glow-in-the-dark paint, and school glue.

Now, school glue is made of something called polyvinyl acetate. And polyvinyl acetate is what’s called a polymer, meaning that it’s a long molecule with a repeating pattern. Now, if you’ve ever used school glue you know that it’s pretty thick and “viscous.” And that’s because the polymers are so long that they can get kinda twisted around each other. But we can make the glue even more viscous and slimy by adding borax.

First, mix half a cup of glue and two tablespoons of paint with two thirds of a cup of hot water. Your slime will be less clumpy if you mix this up really well and don’t leave any glue globs.

Then in a separate bowl, dissolve two teaspoons of borax in a third of a cup of hot water— and again, really mix these two up well so there are as few borax crystals left as possible.

Finally, add two tablespoons of your borax solution to your glue solution.

So, you can see that as I add this, this mixture gets way thicker. And that’s because borate ions in the borax cling to the different polymer chains in the glue and hold them together, making the substance even more viscous and solid.

It’s so cool! But now that we have this awesome slime we want to see it glow in the dark, so we need to charge it up by holding it under a light. And I actually have a light right in front of me, so that’s what I’m gonna do now.

So, why does stuff glow in the dark? Well, usually, when light hits an object, the atoms in that object get excited and their electrons jump up to a higher energy level. But that makes the atoms really unstable, so what they’ll do is they’ll emit light in the form of a photon. And that happens all over the object in a tiny fraction of a second.

But glow in the dark paint contains something called phosphors. When light hits a phosphor, the same thing happens—the atoms get excited and the electrons jump up to a higher energy level. But phosphors have a harder time falling back down to that more stable state. They will eventually emit the photon, but it doesn’t necessarily happen all at once and it can take a longer time. So, that’s why there’s that lingering glow that can last for minutes after being charged up by the light.

Making slime was one of the first experiments I did as a kid that got me really excited about science. But I gotta say, it’s pretty fun as a grownup, too. So definitely try this at home. And let me know in the comments how it goes.




Host, Writer, Editor
Anna Rothschild
Jeffrey Wood
Special Thanks to Dr. Greg Kestin
Best Buds Forever (stripped Vers.)
Music Provided by APM
©WGBH Educational Foundation 2015


(used with permission from author)
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Produced by WGBH for PBS Digital Studios

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