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A solution of polyvinyl alcohol (PVA) can be made into a slime by adding borax solution, which creates cross-links between polymer chains. This experiment is easy to set up, providing the chemicals are available, and should take no more than about 30 minutes. It can be done by students in groups of two or three.
This slime recipe requires a 4% solution of polyvinyl alcohol (PVA) and sodium tetraborate (that’s Borax). Slime made with PVA is often referred to as commercial or “professional” slime. This is the type that is generally found in toy stores.
PROCEDURE: Polyvinyl Alcohol Slime. Materials needed: paper cup, 5 oz stirring rod Polyvinyl alcohol, 4% solution in water. (See “Preparation of Solutions” at the end of this investigation.) Borax (sodium tetraborate decahydrate), Na2B4O7 10H20, 4% solution, weight in water.
Making PVA Solution. Add 30 g or 1 ounce of PVA powder to 500 ml or 16 fluid ounces of cold water in a bowl or double-boiler. Leave it for 1 hour to for the water to absorb the PVA. Put the bowl with this mixture into a saucepan with water or used the double-boiler.
In this experiment, a polymer (polyvinyl alcohol) chemically reacts with borax to form a crosslinked polymer network. Individual polymer chains are formed by covalent bonds, which are strong bonds. In making slime, the individual polymer chains are bound together by weak hydrogen bonds.
There are two methods for preparing a 4% aqueous solution of polyvinyl alcohol, the conventional heating method and the microwave heating method. The microwave method is much easier and less time consuming.
Prepare your materials. Step 1: Dissolve the Polyvinylalcohol in water and make a 4% solution. In a steel or aluminum saucepan add 1250 ml water (5 of the blue measuring cup). Add the entire 50 grams polyvinylalcohol to the saucepann.
