Wednesday, November 30, 2011

Polymers/Purcell/Block I


Polymers
Problem: Find the change in physical properties of a polymer as a result of cross-linking.

Hypothesis: The changes in the property of the polymer will be determined by the size of the polymer.

Materials
500 mL Water
25 mL Elmer's glue
1 tsp. Borax
1 graduated cylinder
1 600 mL Beaker
1 250 mL Beaker
Stirring rod
Procedures:
      Put 100 mL of water into the 600 mL beaker. Next put three teaspoons of Borax into the water and stir. Then pour 25 mL of glue into the 250 mL beaker. Add the Borax solution to the glue and stir.
Once the solution becomes more of a solid, take the solid out. Pour the extra liquid down the drain. Roll the solid into a spherical shape. Next, perform a series of tests. First, describe the polymer(texture, smell). Next, rate the sliminess on a scale of one to five. Then, see what happens when a finger is slowly poking the polymer. Then try it doing it quickly. Next, slowly pull apart the putty. then try doing it quickly. Next, lay the putty down on the table. See how long it takes for the putty to stop flattening. Finally, hold a ruler vertically. Drop the ball of putty onto the table. Record the height of the first bounce.








Add the Borax solution to the glue and stir.         Once the solution becomes more of a solid, take the solid out.



Results:
      On the first test, it was found that the putty was squishy and odorless. The slime rating was two. On the slow poke test, the finger goes in will a little force. The finger does not go in quickly. The slow pull test results in expanding and pulling apart. The putty comes apart easily in the quick pull test. The blob test resulted in 2:06. The bounce test resulted in a fifteen centimeter bounce. The monomers in the glue and the Borax came together to form a polymer.
Conclusion:
     My hypothesis was partly accepted. The Description Test does not rely on the size of the polymer. The Slime Rating does not rely on the size of the polymer. The Slow and Quick Poke Tests did not rely on the size of the polymer. The Slow and Quick Pull Tests partly relied on the size of the polymer. The Blob Test highly relied on the size of the polymer. This is because the time would have been greater if the size of the polymer was greater. Also, the time would have been less if the size of the polymer was less. The Bounce test mostly relied on the spherical nature of the polymer. However, the bounce is measured from the top of the polymer at the highest point. If the putty was smaller, the top of it would not have been as great.


     


Polymers

 
Polymer Basics        Name ___________________________

Use the sites on the Matter & Atoms page of the Kid Zone at http://sciencespot.net/ to complete this worksheet.

Site #1: HandsOn Plastics 
1. Plastics are polymers___________________, which is something made of many ___units____________ similar to a chain. Each
link in the chain is the “___mer___” or basic unit usually made out of ____carbon_________, ____hydrogen________, ___oxygen__________,
and/or _________silicon_____.  To make the chain, many links or units are hooked or _________polymerized____________ together.

2. Many common classes of polymers are composed of ______hydrocarbons_________________, which contain the elements
carbon and hydrogen. List seven elements that are also found in polymers: _____Oxygen_________, _____chlorine_________,
______fluorine________, _______nitrogen_______, ______silicon________, ___phosphorous___________, and ______sulfur________.

3. What is one of the most famous silicon-based polymers? _______Silly Putty________________

4.  What are the general attributes (properties) of polymers?
 A. Polymers can be very resistant to ___chemicals_________________.
 B. Polymers can be both ______thermal___________ and _____electrical____________ insulators.
 C. Polymers are very light in ______mass___________ with varying degrees of _____strength____________.
 D. Polymers can be _______processed__________ in various ways to produce thin fibers or very intricate parts.

5. What percentage of our trash are plastics? _____9.9_____%

6. What does WTE mean? _____waste_______-____to___-___energy________ What are two benefits of WTE? 
 1 – We can use plastics that cannot be ________recycled_____________.
 2 – Incineration of polymers produces ________heat____ _____energy__________. 

Site #2:  History of Plastics
Read the information on this page to help you complete this section. Fill in the blanks with the year it was first
produced and the last name(s) of the person credited with the discovery/development. Use the information to list the
substances with dates from the oldest to the most recent in the box. 

Rayon – Developed in ___________ by ____________________________
Silly Putty - Developed in ___________ by ____________________________
Cellophane - Discovered in ___________ by ____________________________
Parkesine - Discovered in ___________ by ____________________________
Nylon - Developed in ___________ by ____________________________
Bakelite - Developed in ___________ by ____________________________
Velcro - Developed in ___________ by ____________________________
Saran - Discovered in ___________ by ____________________________ 
PVC (Vinyl) – Developed by ____________________________
Polyethylene – Developed in ___________ by _______________ & _______________
Teflon – Discovered in ___________ by ____________________________
Celluoid - Developed in ___________ by ____________________________

Plastics Timeline
Oldest to Most Recent

1_____________________
2_____________________
3_____________________
4_____________________
5_____________________
6_____________________
7_____________________
8_____________________
9_____________________
10____________________
11____________________


Site #3:  Polymers – They’re Everywhere
 Plastics are soft and moldable during their production. The building blocks for making plastics are small organic molecules. They generally come from oil or natural gas but can also come from organic materials such as wood fibers, corn, or banana peels.

Site #4 – Polymer Flash Activities

1. Click the link to make a virtual polymer and choose polyethylene.
 A. What type of monomer is used to make this polymer? ______ethylene molecules______________
 B. What elements and how many of each is in one of these monomers?
  C = _____Carbon_________  # - __4___  H = ______________  # -___1__
 C. What starts the process? _____________________

2. Click the link to try the matching games.  Record your times or scores in the blanks below.
 A. Breakfast Game– 1st Try = _______   2nd Try = _______  3rd Try = _______
B. Polymer Game - – 1st Try = _______   2nd Try = _______  3rd Try = _______


Wednesday, November 16, 2011

Experiment Watching

     Today, the class witnessed combustion, a form of chemical reaction. We witnessed how ethanol reacts to a flame in the form of combustion. The flame and the ethanol were two reactants. These reactants formed a product. The gas escaped out of the bottle and pushed the other way. This was an example of Newton's Third Law of Motion.
     Then we witnessed and experiment with baking soda and vinegar. The gas was introduced to candles. The candles went out. This was because unlike the other experiment, we were not introducing heat. We were introducing the other reactant. This caused the flame to go out.
     Finally we experimented with chlorine, zinc, and fire.He put chlorine and zinc in a beaker and introduced a flame. The mixture gave of a gas and bubbled. this is because the chlorine was flammable. All of these reactants and products were very interesting.

Wednesday, November 2, 2011

Freezing and Melting Water

Problem: What are the freezing and melting temperatures of water. What is the relationship between the two temperatures.
Hypothesis: The freezing temperature of water will be 0 degrees Celsius. The melting point of ice will be 7 degrees Celsius. The relationship will be a seven degree difference.
Materials: computer, 400 mL beaker, Vernier computer interface, water, LoggerPro, 10 mL graduated cylinder, Temperature Probe, ice, ring stand, salt, stirring rod, test tube
Results: