Purpose
To observe the properties of the polymers with different amount of borax to see the effects of cross linking.
Question
How does the amount of a cross linking substances affect physical properties of a polymer
Experimental Design
A polymer was made with precise measuring of all the reactants especially different measurements of Borax solution as it was the key to cross linking. Physical properties of all the polymers were observed and the role of amount of borax in each polymer was seen.
Materials
beakers water 45 ml of white glue few drops of food coloring
___ ml of borax stirring rod
Procedure
1. Measure 45 mL of white glue in 250 mL beaker
2. add equal volume of warm water and a few drops of food coloring and stir the mixture
3. add 15 mL of solid borax in a 400 mL beaker
4. Pour ___ mL of the borax solution into the glue mixture. Stir the mixture quickly
Observations
35 ml of Borax Solution in Polymer
1. The polymer does not ooze
2. somewhat stretches when pulled slowly
3. Breaks when quickly pulled
4. it bounces a bit
5. starts expanding is size and flattening out slowly
6. settles slowly
25 ml of Borax Solution in Polymer
1. the polymer does not ooze
2. stretches a lot
3. when quickly pulled it breaks
4. its bouncy
5. it expands and starts to flatten out
6. settles quickly
30 ml of Borax Solution in Polymer
1. The polymer does not ooze
2. stretches to an extent
3. it breaks when pulled quickly
4. it bounces a bit
5. it expands and flattens slowly
6. settles at a medium rate
Analysis
The amount of Borax solution added to the other reactants determined the physical properties of the polymer. The observations concluded that the more borax solution added to the polymer solution the thicker and stronger it is and the less elasticity it has. The borax solution is what caused the cross linking in the polymer so that means that strong cross