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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.
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.
If desired, one or two drops of food color can be added to the polyvinyl alcohol solution. Stir the mixture. Measure 5 mL of 4% borax solution. Pour the borax solution into the cup of polyvinyl alcohol and stir well. Describe what happens. Remove the material from the cup and knead it in your hand. The material will become firm and lose some of
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.
1. Pour 50 mL of 4% polyvinyl alcohol solution into a 150-mL beaker. Optional: Add a drop or two of food coloring (green will be a big hit!) and stir. 2. Carefully pour 30 to 40 mL of acetone on top of the polyvinyl alcohol solution. It helps if the beaker containing polyvinyl
Demonstrate that variables in preparation can make a big difference in the properties of a product, in this case a mixture of a polyvinyl alcohol or a glue with a borax solution at different compositions.
22 Απρ 2024 · Experimental procedure. Dissolve 1 g of borax in 25 ml of water. Simultaneously, prepare another solution of 4 g of PVA in 100 ml of water. To achieve complete dissolution, it is convenient to gently warm the mixture at a temperature not exceeding 50 ºC.
