Hey there! I’m Emily from MinuteEarth, and today we’re diving into the world of plastics. Plastics are super strong and can be shaped into all sorts of things, from food wraps to parts for airplanes. But here’s the catch: because they’re so tough, plastics stick around in the environment long after we’re done using them. They don’t break down like other materials do.
Plastics are made from repeating chemical units, like ethylene, that form long chains. That’s why many plastics have names starting with “poly,” which means “many” in Greek. Imagine these chains like a bunch of cooked spaghetti noodles all tangled together. This structure gives plastics their strength and flexibility.
Over time, things like heat and pressure can cause big pieces of plastic to break into smaller bits. However, the strong bonds between the carbon atoms in these chains don’t break easily. So, even when plastics break into tiny pieces, they don’t completely disappear.
Scientists are working on making plastics that don’t last forever. One example is polylactide, which is still made of repeating units but uses different bonds, like carbon-oxygen bonds. These bonds can break down more easily, even with just water, allowing bacteria to digest the fragments.
In the right conditions, like a special processing facility, these new plastics can turn into carbon dioxide and water in just a few months. But there are some downsides: polylactide is more expensive and has a lower melting point, which means it can’t be used for everything.
We’re not there yet, but scientists are hopeful about creating the perfect plastic. At the University of Minnesota, researchers like Professor Marc Hillmyer and his team are working on biodegradable plastics made from renewable resources. They’re collaborating with the University’s Center for Sustainable Polymers to bring these eco-friendly plastics closer to being used in everyday products.
Thanks to the University of Minnesota for supporting this research and helping us move toward a cleaner, more sustainable future!
Using colored paper strips, create a model of plastic chains by linking the strips together to form long chains. This will help you visualize how the repeating units in plastics form strong, flexible structures. Discuss with your classmates how these models represent the strength and flexibility of plastics.
Conduct an experiment by placing different types of plastics in various environmental conditions (e.g., sunlight, water, soil) to observe how they break down over time. Record your observations and discuss why some plastics degrade faster than others.
Research and present on biodegradable plastics like polylactide. Explore how they are made, their benefits, and their limitations. Share your findings with the class, highlighting how these materials could impact the environment.
Participate in a debate on the pros and cons of using traditional plastics versus biodegradable plastics. Prepare arguments for both sides, considering environmental impact, cost, and usability. Engage with your peers to explore different perspectives.
Organize a challenge to creatively reuse plastic items that would otherwise be discarded. Work in groups to design and build new products or art pieces from these plastics. Present your creations to the class and discuss the importance of recycling and reusing materials.
Sure! Here’s a sanitized version of the transcript:
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Hi, this is Emily from MinuteEarth. Plastic is incredibly strong and can be molded into a wide variety of products. However, that strength also means plastic remains in the environment long after we no longer need it, as it does not fully break down like most materials.
Each type of plastic is made of a repeating chemical unit, such as ethylene, which forms long strands. This is why the names of plastics often start with “poly,” the Greek word for “many.” These strands get tangled together, similar to cooked pasta, to create everything from food wrap to aerospace materials.
Over time, factors like heat and tension can cause larger pieces of plastic to break into smaller fragments. However, the individual strands are held together by strong carbon-carbon bonds, which are resistant to normal heat and pressure. As a result, while large pieces of plastic can break apart, the smaller pieces do not truly disappear.
Scientists are exploring ways to create less permanent plastics. New versions, such as polylactide, are still made of repeating chemical units, but instead of enduring carbon-carbon bonds, they use different types of links, like carbon-oxygen bonds. These can be easily broken down, even by water, allowing the resulting fragments to be digested by bacteria.
After several years in the environment, or just a few months in the right processing facility, these new plastics can degrade completely into carbon dioxide and water. However, there are some challenges: polylactide is more expensive than traditional plastics, and its carbon-oxygen bonds result in a lower softening point, making it less practical for certain applications.
While we haven’t yet developed the perfect plastic, scientists are optimistic about future possibilities.
This video was sponsored by the University of Minnesota, where students, faculty, and staff across various fields are working to address significant societal challenges. One of these challenges is ensuring clean water and sustainable ecosystems, which includes developing environmentally friendly technologies. In the Department of Chemistry, Professor Marc Hillmyer and his research team, including graduate student Guilhem De Hoe, are creating biodegradable plastics from renewable resources and collaborating with the University’s Center for Sustainable Polymers to advance promising new plastic options toward commercialization.
Thank you, University of Minnesota!
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Let me know if you need any further modifications!
Plastics – Materials made from polymers that can be molded into different shapes and are often used in packaging and containers. – Scientists are working on developing new types of plastics that are more environmentally friendly.
Environment – The natural world, including the air, water, and land, in which living organisms exist and interact. – Protecting the environment is crucial for maintaining biodiversity and human health.
Carbon – A chemical element that is the basis of all known life on Earth and is found in many compounds, including carbon dioxide. – Carbon is a key element in the study of organic chemistry.
Bonds – The connections between atoms in a molecule that hold the atoms together. – In chemistry class, we learned how covalent bonds form between atoms to create molecules.
Biodegradable – Capable of being broken down by natural processes, such as by bacteria, into harmless substances. – Biodegradable materials are important for reducing waste in landfills.
Polylactide – A biodegradable plastic made from renewable resources like corn starch or sugarcane. – Polylactide is used to make eco-friendly packaging materials.
Sustainable – Practices that do not deplete resources or harm the environment, ensuring that they can be maintained over the long term. – Using sustainable energy sources like solar and wind power helps protect the environment.
Chemical – A substance with a distinct molecular composition that is produced by or used in a chemical process. – The chemical reaction between vinegar and baking soda produces carbon dioxide gas.
Researchers – Scientists who conduct studies and experiments to discover new information and solve problems. – Researchers are developing new methods to recycle plastics more efficiently.
Flexibility – The ability of a material to bend or be shaped without breaking. – The flexibility of certain plastics makes them ideal for use in a variety of products.
