Monday, April 13, 2020

PVA and Sodium Borate Crosslinks Essay Sample free essay sample

A 5 to 1 ratio of PVA and Na borate creates crosslinks with the polymer to bring forth a ball-like solid without compromising the coveted ability to resile. stretch and maintain form through utmost temperature. Introduction:Polyvinyl intoxicant is a polymer that when combined with Na borate creates covalent crosslinking bonds between the polymers. which change the solution from a liquid into a jelly-like solid that can be formed into a ball. 2 A polymer is a concatenation made of units combined in the same linkage throughout the full substance. 2 Polymers are used extensively in today’s universe to make paper. motorcycle tyres. plastic. PVC and many other family common points. 3 The bonds in the polymer are cross-linked ; therefore the ball should be flexible and have the ability to stretch well. 2 Due to the fact that the Na borate is the solution that causes hydrogen bonds. which do non keep the ball together. we can presume that the greater sums of Na borate will do the ball to hold unsought belongingss and fall apart. We will write a custom essay sample on PVA and Sodium Borate Crosslinks Essay Sample or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page ? By maintaining the sum of borax used changeless and altering the sum of PVA the experiment should demo which ratio is better suited for the end of making a ball. The ball needed to be able to resile. non fall apart. be flexible but come back to its original form after stretching. be atoxic. odorless. and easy to do in order to take down fabrication costs. After happening the top two ratios they will be tested in cold and hot conditions that are similar to the countries in which the balls will be shipped. The ice bath represents Alaska and the hot bath represents New Mexico. The undermentioned image shows the crosslinking between the PVA and Na borate. The borate ion has bonded with the hydroxyl ( OH ) groups of the polymer and links them together. ? The molecular expression of PVA is [ -CH2CHOH- ] N and the chemical construction of Na borate is Na2B4O7. DiagramBorate ions crosslinking with the PVA ironss. While executing the experiment safety goggles should be worn at all times and baseball mitts should be worn at all times while pouring the solutions and managing the gel. Do non savor the gel or acquire it on your apparels because it can stain. ? Procedure for Experiment 1: 1. In three separate 10 milliliter graduated cylinders step out 10 milliliters PVA. 8 mL PVA and 6 milliliter PVA. 2. In three separate 10 milliliter graduated cylinders step out 2 milliliters sodium borate. 2 mL Na borate and 2 milliliter Na borate. 3. In one 250 milliliter beaker combine 10 milliliter PVA and 2 milliliter Na borate. 4. For a minute hold the beaker and twirl it so the contents can unite. Put to the side. 5. In a 250 milliliter beaker combine 8 milliliter PVA and 2 milliliter Na borate. 6. For a minute hold the beaker and twirl it so the contents can unite. Put to the side. 7. In a 250 milliliter beaker combine 6 milliliter PVA and 2 milliliter Na borate. 8. For a minute hold the beaker and twirl it so the contents can unite. Put to the side. 9. Taking the first beaker that is keeping the 10 milliliter PVA and 2 milliliter Na borate scoop out the contents with your manus and for 20 seconds roll your custodies together to organize a ball with the gel. 10. Test its bou nciness ability by dropping it on the tabular array and utilizing a swayer mensurating how high it bounced. Record. 11. Test its ability to stretch by keeping it between two fingers and swinging above the tabular array. Use a swayer to enter how long it stretches before interrupting. Record. 12. Repeat stairss 9-11 with the other two beakers and their contents. After seeing the consequence we decided to seek one more ratio that had the lowest sum of Na borate. 1. In a calibrated cylinder step out 6 milliliters PVA. 2. in a calibrated cylinder step out 1 milliliters sodium borate.3. In a 250 milliliter beaker combine the 6 milliliters PVA with the 1 milliliter Na borate. 4. For a minute hold the beaker and twirl it so the contents can unite. 5. Scoop out the contents by manus and for 20 seconds roll your custodies together to organize a ball with the gel. 6. Test its bounciness ability and stretch ability like the old experiment. Record. Procedure for Experiment 2: Making the Balls:1. Measure out 6 milliliters of PVA into a calibrated cylinder. step out 10 milliliter PVA into another graduated cylinder. 2. Measure out 2 milliliters of Na borate into a calibrated cylinder. step out 1 milliliters sodium borate into another graduated cylinder. 3. In one 250 milliliter beaker pour the 6 milliliter PVA so add the 1 milliliter Na borate. 4. For a minute hold the beaker and twirl it so the contents can unite. Put to the side. 5. In one 250 milliliter beaker pour the 10 milliliter PVA and so add the 2 milliliter Na borate. 6. For a minute hold the beaker and twirl it so the contents can unite. Put to the side. 7. Repeat stairss 1-6. This will ensue in two balls of the 6 milliliter PVA and 1 milliliter Na borate and two balls of the 10 milliliter PVA and 2 milliliter Na borate. Ice Bath: 1. While the contents are resting set up an ice bath. in a 400 milliliter beaker fill middle with ice and so add H2O to the top marker. 2. Put up a thermometer base and lodge the terminal of the thermometer into the ice H2O. 3. The H2O should be at 1Â °C. Keep ticker of the thermometer readings and add ice to maintain it at a steady temperature. 4. Using the beaker with the solution of 10 milliliters PVA and 2 milliliter borax. lift out out the contents with your custodies and for 30 seconds roll it into a ball. 5. Once the ball is formed topographic point it into the ice bath that should be at 1Â °C. 6. Let sit for 2 proceedingss and record any alterations you observe. 7. With your custodies pull the ball out of the ice bath. Record any alterations in the manner it feels. 8. Test its resiling ability by dropping it a foot high above the tabular array and utilizing to ruler to mensurate the tallness it bounced. record observations. 9. Keep the ball in one manus and see how far it s tretches utilizing a swayer when allowed to swing. Record. 10. Repeats steps 1-6 utilizing the solution of 6 milliliters PVA and 1 milliliter borax. Heat Home plate: 1. While your contents are resting set up a hot bath. in a 400 milliliter beaker fill to the top marker with H2O. 2. Topographic point beaker on a hot home base and set to a scene of four. 3. Put up a thermometer base and lodge the terminal of the thermometer into the H2O. 4. The H2O should be at 35Â °C. set the heat scene as the experiment continues in order to maintain it at a steady temperature. 5. Using the 2nd beaker with the solution of 10 milliliters PVA and 2 milliliter borax. lift out out the contents with your custodies and for 30 seconds roll it into a ball. 6. Once the ball is formed topographic point it into the hot bath that should be at 35Â °C. 7. Let sit for 2 proceedingss and record any alterations you observe. 8. With your custodies and a stick if needed pull the ball out of the ice back. Record any alterations. 9. Test its resiling ability by dropping it from a pes above the tabular array and utilizing a swayer to mensurate the tallness it bounces. record observa tions. 10. Keep the ball in one manus and see how far it stretches utilizing a swayer when allowed to swing. Record. 11. Repeat stairss 1-6 utilizing the solution of 6 milliliters PVA and 1 milliliter borax. 10 Minute Cold Water Experiment: 1. Fill two 400 milliliter beakers halfway with ice. so to the top line with H2O. 2. Put up two thermometers. set one thermometer into each beaker. 3. The temperature should be at 1Â °C. add more ice as needed throughout the experiment so the temperature is steady. 4. Take both the 10 milliliter PVA: 2 milliliter Borax ball and the 6 milliliter PVA: 1 milliliter Borax ball from the old cold H2O experiment and set them into their separate beakers. ( Make sure to take note which ball goes into which beaker ) 5. Let sit for 10 proceedingss entering any alterations. do certain temperature is changeless. 6. Remove both balls from the H2O with custodies. 7. Perform the bounciness trial on each. record.8. Perform the stretch trial on each. record.Datas:Experiment 1: Finding the Best RatioSolution| Color/Texture| Bounce Test| Stretch Test| Other Observations| 10 milliliter PVA2 milliliter borax| Clear/cold to touch and gelatinlike | Bounced 2 inches| 14 inches| In the beaker formed a gel but with liquid left over environing it. Went back into its ball form after being stretched. Didn’t stick to custodies or tabular array. | 8 milliliter PVA2 milliliter borax| Clear/cold to touch and gelatinous| Bounced 1 inch| 7-1/2 inches| In the beaker formed a gel but with liquid left over. had less liquid than the 10 PVA: 2 Borax solution. Fell apart after being stretched. | 6 milliliter PVA2 milliliter borax| Clear/cold to touch and gelatinous| Did non bounce| 2 inches| Formed into a jelly with no liquid left over. stuck to bottom of container and doesn’t move about. Stretched 2 inches and stuck to baseball mitts. | 6 milliliter PVA1 milliliter borax| Clear with little white coloring/cold to touch and gelatinous| Bounced 2 inches| 11 inches ( but stretched really easy ) | Formed a gel with really small liquid left over. after stretching it formed back into a ball. In experiment one we foremost believed that the ratio of 6:2 ( PVA to SB ) would be the best because it had no liquid left over which means we wouldn’t be blowing solution. However when organizing the ball the solid absorbed the liquid and formed a ball that could be flexible and ductile. From experiment one we concluded the two best ratios were of the 5:1 and 6:1 and were traveling to be tested for their behaviour in utmost temperatures. Experiment 2: Testing Exposure to Cold ( Alaska )Solution| Time in Ice Bath| Color/Texture| Bounce Test| Stretch Test| Other Observations| 10 milliliter PVA. 2 mL Borax| 2 minutes| Same colour ( clear ) /slimy| Doesn’t bounce| 15 cm| Slightly breaks when bounced. but instantly comes back together. as it warms up from custodies it starts to be able to resile once more. Within a minute of room temperature it is back to normal. | 6 milliliter PVA. 1 mL Borax| 2 minutes| Same colour ( clear ) /slimy| Bounces really somewhat. 1 inch| 30 cm| Slightly breaks when bounced ( but non every bit much as 10:2 ball ) . but instantly comes back together. as it warms up from custodies it starts to be able to resile once more. Within a minute of room temperature it is back to normal. By proving for cold for two proceedingss we saw how each ball would respond when in the cold for a short period of clip. such as if a child was walking from the auto into the house. Both were satisfactory and able to come back to its original form and belongingss. Testing Exposure to Heat ( New Mexico ) Solution| Time in Hot Bath| Color/Texture| Bounce Test| Stretch Test| Other Observations| 10 milliliter PVA. 2 mL Borax| 2 minutes| Same colour ( clear ) /very slimy. gooey| Can non finish bounciness test| Can non finish stretch test| Turned to goo about instantly. sinks to bottom into an egg-shaped form. can non be pulled out because it merely falls apart into the water| 6 milliliter PVA. 1 mL Borax| 2 minutes| Same colour ( clear ) /very slimy. gooey| Can non finish bounciness test| Can non finish stretch test| Turned to goo about instantly. sinks to bottom into an egg-shaped form. can non be pulled out because it merely falls apart into the water| By proving for heat we were able to find if the balls could manage the temperature of New Mexico where they were being shipped from. From the consequences we can reason that neither of the ratios are able to keep their form when exposed to higher temperatures. Testing Drawn-out Exposure to ColdSolution| Time in Ice Bath| Color/Texture| Bounce Test| Stretch Test| Other Observations| 10 milliliter PVA. 2 mL Borax| 10 minutes| Same colour ( clear ) /slimy| Doesn’t bounce| 32 cm| When bounced it instantly breaks and doesn’t come back together on its ain. it can be rolled back into a ball form for the stretch trial. As it warms up it begins to be able to resile once more. | 6 milliliter PVA. 1 mL Borax| 10 minutes| Same colour ( clear ) /slimy| Bounces really somewhat. 1 inch| 45 cm| Slightly breaks when bounced ( but non every bit much as 10:2 ball ) . but instantly comes back together. as it warms up from custodies it starts to be able to resile once more. Within a minute of room temperature it is back to normal. | By maintaining the balls in the H2O for an drawn-out sum of clip we were able to see how cold affected their belongingss. The 6:1 ratio was somewhat stronger and maintained and regained its form faster. Decision: By uniting legion ratios of PVA and borax the most effectual combination was of the 6 milliliter of PVA and 1 milliliter borax. It non merely uses the least sum of each solution which would optimise fabrication costs but it retains its ability to resile and stretch when put through extreme cold temperatures. However this merchandise will non work good in hot countries such as New Mexico. The heat from the H2O caused the viscousness of the merchandise to alter ; it fell apart in the H2O and could non be handled. it merely slips off of the setup being used to draw it out. Once the H2O is poured out of the beaker and the merchandise was allowed to chill it lodge to the surface it was on and did non travel back to its original ball-like form. Originally the combination of 6 milliliters PVA and 2 milliliter borax was believed to be the best combination because it did non hold liquid left over in its beaker ; nevertheless the borax caused the merchandise to lose some of its belongingss tha t come from the polymer PVA. It lost its flexibleness wouldn’t signifier into a proper ball. Research: Polymers. particularly polyvinyl intoxicant. are highly utile in today’s universe and in medical specialty. By utilizing the known belongingss of PVA scientists can expect how it will respond with other solutions and utilize these hypothesis’ to develop new merchandises. That is what we did in this lab. cognizing Na borate creates crosslinks with the ironss in PVA we were able to plan a ball that could keep its form but remain ductile. In today’s scientific discipline PVA is being used to make transdermic spots. encapsulation of systems that deliver drugs and in dressing of lesions. Citing: 1Nuffield Foundation. hypertext transfer protocol: //www. nuffieldfoundation. org/practical-chemistry/pva-polymer-slime 2RSC: Advancing the Chemical Sciences. hypertext transfer protocol: //www. rsc. org/Education/EiC/issues/2005_Jan/exhibition. asp 3Materials Science. hypertext transfer protocol: //dsc. find. com/tv-shows/curiosity/topics/polymer-based-products-you-use-every-day. htm ?Basque Research. hypertext transfer protocol: //www. basqueresearch. com/berria_irakurri. asp? Berri_Kod=3894 A ; hizk=I ?Slime A ; Superballs. hypertext transfer protocol: //icn2. umeche. Maine. edu/newnav/Homepage/Highschool/Slime/lecpolymers2. htm 6Science of Slime. hypertext transfer protocol: //www. ccmr. Cornell. edu/education/modules/documents/ScienceofSlime_student. pdf