Kids, how would you like to combine elements from both science and art to make a simulated stained glass?  For artists, creating the right material (whether it is a painting or a sculpture or whatever) requires much experimentation until the result is exactly what they want.  For some scientists this same principle holds when making a particular molecule, for example, although different tools and media are used.  In this activity, you can experiment with the look of a colorful art material. 

Please note:  All chemicals and experiments can entail an element of risk, and no experiments should be performed without proper adult supervision.

First, put about 1 tsp Elmer’s glue in a small plastic cup.  Add about ¼ tsp water and mix with a popsicle stick.  Pour the glue-water mixture into a yogurt cup lid or other plastic lid, or a Styrofoam bowl.  Tilt the lid or bowl all around until the glue solution completely covers the inside surface. Next place two or three drops of differed food coloring onto the glue surface.  Now, off to the side, put a small amount of liquid dish detergent in a small cup.  Touch a toothpick into the detergent, getting just a very small amount, and then touch the center of each food coloring droplet and quickly remove the toothpick.  Do not stir.  What happens?

Your glue has water in it plus long-chain molecules called polyvinyl acetate.  When the food coloring drops are added, they do not spread out much because of the polymer.  (Try adding food coloring to a plain cup of water and you’ll see that it rather easily spreads out).  When the detergent is added, the food coloring begins to spread out into the glue.  This is because detergent molecules lessen the "pull" (the surface tension) between water and polymer molecules.  The chemical word for soap that helps to describe this action is "surfactant".  Experiment by touching the food coloring drops with more detergent, or with more or less colors to get the effect that you are looking for.

Think about this… Colored glass has been used for centuries to make beautiful stained glass windows.  Glass makers use different combinations of chemicals to produce the many different colors of glass.  Wonderful works of art are created by variations in the design, the colors, and the effect of light passing through the material.  Can you think of a way to use your stained “glass” glue to make a design that light can shine through? Hint: wax paper might be a good surface to work on.  Good luck!

Bonus information… Some of the pigments used to color glass are:  cobalt oxide (CoO) makes blue, calcium fluoride (CaF₂) makes milky white, gold (Au) or cuprous oxide (Cu₂O) or selenium (Se) all make red glass.  To make glass green, either iron sulfate (FeSO₄) or copper (Cu) or chromium oxide (Cr₂O₃) are used.  Amber glass is colored by a mixture of carbon (C) and iron sulfide (FeS).  See the 12/96 issue of ChemShorts for an entire column devoted to glass itself.

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Kathleen Carrado Gregar, PhD, Argonne National Labs 
[email protected]
September 2005

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Reference: “WonderNet! – Chemistry and Art” activity at: www.chemistry.org/portal/a/c/s/1/wondernetdisplay.html?DOC=wondernetactivitiesartstainedglass.html