What happens when borax is added to PVA?
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.
How do you make a PVA solution?
To prepare the PVA solution, 4 g of PVA were added to 100 ml distillated water. The mixture was heated and stirred vigorously until all the PVA was dissolved in the water. This took about half an hour. Peptisation was done by addition of 5 ml 1M HNO3 to the solution.
What does PVA and sodium borate make?
A solution of polyvinyl alcohol (PVA) can be made into a slime by adding borax solution, which creates crosslinks between polymer chains. In this activity, some interesting properties of the slime are investigated.
Why does adding acid to PVA borate slime breaks the cross-linking?
Throw a small piece onto a hard surface; it will bounce slightly. Adding acid to the slime breaks the crosslinking producing a liquid with lower viscosity. Adding alkali reverses the process and the slime should be regenerated.
How do you make a 4% sodium borate solution?
Procedure:
- Create a 4% borax solution by measuring 1 cup (240mL) of water and add 1tsp (5ml) of borax powder.
- In a separate container, create a 50/50 glue/water solution. Measure out 1/2 cup of glue and add the same amount of water.
- Stir the glue mixture with the borax solution until it is compltely done. (
Why can PVA gels flow?
In the aqueous borax solutions of PVA, the gelation process occurs through intermolecular hydrogen bonds between hydroxyl groups on PVA chains because of the intervention of a borate anion. The crosslinking points are therefore exchangeable, which results in the gel flowing extremely slowly.
Can you make slime with PVA glue and water?
To make the slime simply pour the PVA glue into a bowl and add the water, mixing until fully incorporated. To this mixture add your favourite food colouring, mixing until you reach your desired colour. At this point, you can also add any embellishments you desire, such as glitter or sequins!
How to prepare a PVA solution?
Measure out 80 g of low MW PVA and add this slowly to the beaker of water, with stirring. In each case, heat the mixture gently, stirring occasionally, until the solution clears. Avoid boiling the solution.
How much PVA is in a glass of water?
That is 40.0 grams of PVA per 960 grams (milliliters) of water. The best results are obtained by heating the water to about 80oC on a hot plate with magnetic stirrer. Sprinkle the PVA powder in very gently and slowly on the top of the solution while stirring so as not to cause the mixture to clump together.
How do you mix polyvinyl alcohol with PVA?
The Polyvinyl Alcohol as a solid is mixed in water to make a 4% solution. That is 40.0 grams of PVA per 960 grams (milliliters) of water. The best results are obtained by heating the water to about 80oC on a hot plate with magnetic stirrer.
Can you mix PVA and borax to make clear PVA?
If you start with clear PVA solution, you can make any variation you want. Measure 2 ounces (60 mL) of PVA into a plastic cup. Add 1 ounce (30 mL) of the Borax cross-linker solution and stir. After several minutes of stirring, all of the PVA should be stuck together in one large clump on the stirring stick.