Making Bioplastic www . GrowingYourFuture . com
Students will examine renewable and nonrenewable resources with a hands-on exploration of bioplastics made from corn .
Materials :
• 1 tablespoon ( 24g ) cornstarch
• 2 drops corn oil
• 1 tablespoon ( 15 mL ) water
• 2 drops food coloring
• Sandwich-sized resealable plastic bag
• Tablespoon measuring spoon
• Microwave
Renewable resources are either naturally reproduced at a sustainable rate or they can be produced in agriculture at a rate equivalent to the demand or need . Nonrenewable resources are made naturally by the Earth but do not renew themselves fast enough for people to count on having the resource for an indefinite period of time . Although plastic is typically considered to be a nonrenewable resource because it is made from petroleum , there is a method of making plastic that can be renewable . Bioplastics are made from biological materials — plant starches , cellulose , oils , or protein .
Procedure : Part 1 1 . Measure 14 g ( 1 tablespoon ) of cornstarch into your plastic bag . 2 . Add 15 ml ( 1 tablespoon ) of water to the cornstarch . 3 . Add 2 small drops of corn oil to the mixture in your bag . 4 . Add 2 drops of food coloring to the mixture in your bag . 5 . Seal the bag and squish it gently to mix everything together .
Describe the mixture in your plastic bag : _______________________ ________________________________________________________ How does it feel when you slowly squish the bag ? _______________ ________________________________________________________ Does it feel the same when you squeeze the bag quicker / harder ?___ ________________________________________________________
Is your mixture a solid or a liquid ? ____________________________ Procedure : Part 2
6 . Microwave your mixture on high power for 20 seconds . Be sure to leave the bag open a tiny bit so that steam can escape . Be careful , the bioplastic will be hot !
7 . Let it cool for several minutes . While it is cooling answer the questions below .
What does your new substance look like ? How is it different from the mixture you started with ? ________________________________
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If your plastic is cool , knead it with your hands . What does it feel like ? Describe its other properties .____________________________
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What could you make with your bioplastic ? What couldn ’ t you make ? Why ? ______________________________________________
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What is used to make bioplastic ? _____________________________ ________________________________________________________