Introduction: The topic for the experiment was using polymer chemistry to develop the best suitable material for a bouncing ball. Within the experiment, three chemicals were given to test for the best material. The three chemicals were chemicals sodium borate (4% m/v), polyvinyl acetate, and polyvinyl alcohol (4% m/v). Polyvinyl acetate and polyvinyl alcohol are both polymers. Polymers are many molecules bonded together using the same linkage, which then forms a chain like structure1. These chain like structure will react with the sodium borate to form cross linked polymers. When sodium borate is dissolved in water it has the reaction of B(OH)4-, which helps react with the polymer substance1. Polyvinyl acetate was not used because it doesn’t …show more content…
First 50mL of polyvinyl alcohol and 50mL of sodium borate were separated, the sodium borate into a glass beaker and the polyvinyl into a plastic beaker. Then in order to find the best suitable material, different ratios of polyvinyl alcohol to sodium borate were mixed. All ratios of the substances were mixed for approximately five minutes and all ratios were performed three different times for a total of three trials per ratio. When rolling up the substance it is necessary to wear gloves in order to take safety precautions between the hazardous substances. A 1:1 ratio (2.5mL PVA to 2.5ml Borax) of polyvinyl alcohol and sodium borate were mixed into a 100mL beaker. It was then removed from the beaker and rolled up into a ball using corn starch that way the new substance could maintain its shape for a longer period. After the substance was rolled into a ball, the bounce height, number of bounces, and elasticity was measured. The bounce height was measured by dropping the substance from a meter height and recording its peak in height after the first bounce. While the bounce height was being measured, so were the number of bounces. In order to have a more precise measurement a camera was used to video the trials. Elasticity was measured by placing the ball on a paper, then drawing a circle around the substance. …show more content…
Three different ratios were tested and the best ratio moved on to the next stage to see how it would suffice to different environmental factors. The results that would determine the best ratio would be a higher bounce height, higher amount of bounces, and a lower elasticity. During week 1, which was the week that different ratios were experimented, the 4:1 ratio had the best results. In Table 1, the average bounce height was 8 inches for the 4:1 ratio. It had over a 3 inch average bounce height compared to the 8:1 ratio, which had the second best results. The 4:1 ratio also had a higher amount of bounces throughout the 3 trials with a total of 10 bounces. A ball’s bounce correlates directly with its elasticity3. The elasticity makes a ball regain its shape quicker after it impacts the ground. The 8:1 and 4:1 ratio had the lowest elasticity and produced the most amount of bounces. However, the 4:1 ratio held its shape better after the impact which allowed it to have a higher bounce than the 8:1 ratio. The 1:1 ratio had the highest elasticity and had the worst