Polymer Lab Group Investigation

In the borax-polymer lab today we combined glue, water, and borax. We also added another ingredient, corn starch which caused the result to become stickier and softer. As well as adding corn starch we adjusted the glue and water amounts a little to have less water so that it would be more of a solid. My hypothesis for this lab was, adding cornstarch would make the ball more solid and less of a soft liquid that when set down for a minute would spread into a puddle. When they were mixed together in the right amounts they formed a white sticky substance that we related to marshmallow fluff. We then picked up the fluff and started to knead it into a ball. Halfway through the process we decided to split it in half and put one in the fridge and continue to knead the first ball. We tested it for three things, density, elasticity, and rebound. Our results were, density- soft, elasticity- at least 2 feet, rebound- less than 2 cm. Some of the results were expected but for the rebound of only 2 cm. I was surprised at how little it bounced, for how soft and move able it was I expected at least 6 or 7 cm. About 10 minutes later, we pulled out the chilled ball and tested it for the same things. Our results were, density- soft (softer than the other), Elasticity- 1 foot or more, rebound- 2 cm. Once again I was surprised about the rebound, the others were expected. Considering the ball had been chilled, to me it seemed like it should have bounced a lot more because of it becoming more of a whole and it should stay together more, but it just didn't bounce like I thought it would. In conclusion, the changes in our tests aloud the ball to become softer and stretchier but dramatically dropped in bounce. Maybe next time we could use more water and less cornstarch, but thats just another hypothesis.