*Note: This is an abbreviated Project Idea, without notes to start your background research, a specific list of materials, or a procedure for how to do the experiment. You can identify abbreviated Project Ideas by the asterisk at the end of the title. If you want a Project Idea with full instructions, please pick one without an asterisk.
There are three different kinds of polymers used for kitchen plastic wrap: polyethylene (e.g., Handiwrap or Glad Wrap), polyvinyl chloride (e.g., Reynold's Plastic Wrap) and polyvinylidene chloride (e.g., Saran Wrap, which is almost 90% polyvinylidene chloride). Which of these materials is least permeable to oxygen? When you slice an apple, the surface of the slice turns brown as the apple is oxidized. Can plastic wrap seal out oxygen and prevent the apple from browning? Which plastic wrap works best? Do background research on the different polymer types used for plastic wraps in order to develop a hypothesis. Use samples of each type of plastic wrap to cover 9 apple slices (3 slices for each wrap). Cut the wraps with a scissors so you don't stretch the material. Prepare your materials in advance so that you can wrap each slice right after it is cut, since oxidation starts immediately. Keep 3 slices unwrapped as controls for comparison. Compare the slices at regular intervals and note your results. You may want to take pictures to use for your display board. Do you think you would get the same results at a different temperature? How about if the slices were on saucers covered with plastic wrap? Does stretching the plastic make any difference? Can you think of other ways you might test oxygen permeability of plastic wraps? (Goodstein, 2004, 65–69)
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If you like this project, you might enjoy exploring these related careers:
Materials Scientist and Engineer
What makes it possible to create high-technology objects like computers and sports gear? It's the materials inside those products. Materials scientists and engineers develop materials, like metals, ceramics, polymers, and composites, that other engineers need for their designs. Materials scientists and engineers think atomically (meaning they understand things at the nanoscale level), but they design microscopically (at the level of a microscope), and their materials are used macroscopically (at the level the eye can see). From heat shields in space, prosthetic limbs, semiconductors, and sunscreens to snowboards, race cars, hard drives, and baking dishes, materials scientists and engineers make the materials that make life better.
Chemical engineers solve the problems that affect our everyday lives by applying the principles of chemistry. If you enjoy working in a chemistry laboratory and are interested in developing useful products for people, then a career as a chemical engineer might be in your future.
Commercial & Industrial Designer
Have you always loved art? Do you have a good eye for beauty, balance, and form? How would you like to see your designs show up in toy stores? Or in a sporting goods store? Or at a car dealer? Commercial and industrial designers create the shape and form of every type of manufactured good that you can think of—from toys, sporting goods, and medical equipment to high technology products, furniture, toothbrushes, and toasters. They design the form of new products that are as beautiful and pleasing to look at as they are functional.
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