Others Like “Biodegradable Plastics” (top 20 results)
Some plastics undergo an unusual transition, from a hard, glassy state to a soft, rubbery state, with increased temperature. For this project, you should do background research on the effects of temperature on different types of plastics. Make sure that you understand the difference between thermosetting and thermoplastic polymers. You should also look for information on the glass transition temperature (Tg) for different plastics. Pure polyvinyl acetate has a Tg of 28 C (about…
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Our forests are a very important natural resource that need to be managed wisely. We use wood products for many different purposes: building materials, paper, cardboard, furniture, fuel, etc. How can we use wood products in a sustainable manner? You can do experiments that examine the growth time of different tree species to see which are good candidates for tree farming. Which types of lumber are most sustainable? You can also compare the effects of clear cutting vs. thinning a forested…
You've seen that a magnet's attractive force can cause a small object (like a paper clip) to "jump" to the magnet. So a magnetic field can act through the air, but what about other materials? Here's an experiment you can do to find out. You'll need a strong bar magnet, a stack of books, a paper clip, some thread and tape. Place the bar magnet underneath the top book in your stack, so that it sticks out. Tie a piece of thread (as long as the stack of books is high) to a paper clip. You…
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Did you know that you can make a simple hygrometer (a device for measuring the relative humidity of the air) with hair? Search online for instructions to build one. Does the type of hair used in the hygrometer affect the accuracy of the results? Do some types of hair respond faster than others? Do some types of hair give a larger (or smaller) response? You could get hair samples from classmates, or a local beauty shop. Use hair samples of equal length to construct each hygrometer. To force…
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You can model this with an ice cube sliding down a plank: how high do you need to lift the end of the plank before the ice cube starts to slide? Try this with one side plain wood and the flip side waxed wood (use paraffin wax, candle wax or ski wax). Make sure both sides are equally smooth to start with. Do at least three trials. More advanced: using what you know about the forces acting on the ice cube, derive equations to calculate the coefficient of friction for each case. Variation:…
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Whipped egg whites are used in many sweet and savory recipes. They are used to add air into cake batters, meringues, and soufflés. Egg whites, also known as albumin are 15 percent protein dissolved into water. When egg whites are beaten or whipped, the protein chains unravel. This is called denaturation. The process of whipping egg whites adds air to the mixture, in addition to denaturing the proteins. The denatured proteins create bonds with each other and trap air bubbles within…
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This project can apply to soccer, hockey, baseball and many other sports. What is the effect of stopping the kick/shot/swing at the moment of impact vs. following through? Think of a way to measure the outcome in each case, and explain your results. (idea from Gardner, 2000, 83-85; for more information with regard to specific sports, see: Barr, 1990, 12-14; Gay, 2004, 142-144; Adair, 2002, 30.)
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There are three different kinds of polymers used for kitchen plastic wrap: low density polyethylene (LDPE) (e.g., Handiwrap or Glad Wrap), polyvinyl chloride (PVC) (e.g., Reynolds PVC Foodservice Wrap or Boardwalk PVC Food Wrap Film) and polyvinylidene chloride (PVdC) (note: Saran Wrap used to be made with polyvinylidene chloride, but has switched to polyethylene. You will need to search for another brand that uses PVdC if you want to test it). Which of these materials is least permeable to…
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There are currently two different kinds of polymers used for kitchen plastic wrap: low density polyethylene (LDPE) (e.g. Saran or Glad Wrap) and polyvinyl chloride (PVC) (e.g. Reynolds PVC Foodservice Wrap or Boardwalk PVC Food Wrap Film). Which of these materials is less 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…
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If you're interested in analyzing how things break, check out the Science Buddies project Fractography: The Way Things Break.
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