Chemistry Science Fair Projects Homemade Bio Polymers

Here’s a fun science experiment to try that’s sure to raise a few eyebrows.  Making your own bio-polymer, or “bio-plastic,” from household items.  It’s a biodegradable idea that’s starting to become popular as both a hobby and a serious attempt to replace plastics made from petroleum.  And, while easy to do, it looks very impressive.

First, assemble your ingredients.  To make bio-polymers you will need: water, starch, glycerin, vinegar, and baking soda.  Glycerin may be the one ingredient you need to run to the store for.  Otherwise, you should have everything already in your kitchen.  Don’t have starch in a box?  No problem.  Potatoes are an excellent source of starch.  Take two potatoes, peel, and cut up into cubes.  Run them through a blender with a half cup of water.  When it’s potato mush, strain out the water using a coffee filter or cheesecloth, leaving nothing but the mashed potato.

Now for the baking.  Put two tablespoons of water and one half teaspoon of baking soda into a small bowl and set it aside.  In a small saucepan set over low heat, mix together seven tablespoons of water, one tablespoon of starch or the potato mash, two teaspoons of white vinegar, and two teaspoons of glycerin.  Mix these together until they start to thicken.  Then add the baking soda/water mix and continue to stir.

Let the mixture boil for ten to fifteen minutes.  This is plastic your mixing, so stir it continuously to keep it from burning or sticking to the pan.  Your mixture will become thicker and glue-like.  That’s when you know it’s ready.

Pour the bio-polymer mix onto a sheet of aluminum foil.  It’s hot, be careful!  Let it dry on the sheet for about a day.  Or, bake it in your oven for one to two hours at 120 degrees.  And there you have it.  A sheet of plastic.

Try these tips to get more creative with your creation.  When mixing, you can add five to six drops of food coloring to make the plastic colorful.  Pour the plastic into cookie cutters placed on the aluminum to make shapes.  Pour them into shaped ice-cube trays (although they’re a bit hard to get out).  The plastic can be molded and shaped in any variety of ways.  Try pouring it into a picture frame or similar box-shape placed on the aluminum to make squares, and then stacking the squares into cubes.  Pour it in a thin layer into a metal pie pan or similar shape, and you can make dinner plates!  There are many ways to use this bio-polymer that are both impressive and useful, limited only by your imagination.

There are some things to remember while doing this.  You are cooking plastic, so do this in a well ventilated space.  Open a window if possible.  Do not re-use the pan for anything except making more bio-polymer.  When drying, understand that the bio-polymer will shrink some which may cause warping or mis-shapen forms.  It may also try to stick to the aluminum foil, so try spraying the aluminum foil with cooking spray before starting.  The bio-polymer will harden quickly, so clean the pan and any surfaces it spills onto immediately.  And even though it is bio-degradable, don’t try to eat it!

Because it is biodegradable, it will eventually become brittle and brake apart.  Be sure to tell people that when that happens, it’s time to make more!  Good luck!