Plastic

Today, there are seven basic types of plastics. PET, Polyethylene Terephthalate, holds our water and soda bottles, bottle caps, and jars. JDPE, High-Density Polyethylene, stores our shampoo and provides single-use grocery bags. PVC, Polyvinyl Chloride, holds cleaning products and is available in sheets! LDPE, Low-Density Poly Ethylene, bags or bread and provides plastic films. PP, Polypropylene, holds our yogurt and is the plastic for straws and hangers. ** PS, or Poly Styrene*, makes up takeaway and rigid packaging and is formed into millions of toys! *Other plastics** constitute Baby bottles, CDs, and stockings.

PET (Group 1): Plastics in group one are made from polyethylene terephthalate, or PET for short. PET is useful because it’s used a lot for packaging food and drinks. It’s strong and keeps oxygen out, which helps keep the food fresh. PET bottles are the most widely recycled plastic in the world!

HDPE (Group 2): HDPE, or High-Density Polyethylene, is a challenging and durable plastic used for grocery bags, milk jugs, recycling bins, playground equipment, lids, and shampoo bottles. It’s vital because its long, unbranched polymer chains can handle high temperatures up to 120 °C without changing shape. HDPE is widely recycled because it’s one of the easiest plastics to recycle.

PVC (Group 3): PVC, or Polyvinyl Chloride, is the third most widely produced synthetic plastic. It comes in two primary forms: rigid and flexible. Rigid PVC is used in the construction industry to make door and window frames and pipes for drinking water and wastewater. When mixed with other things, PVC can become softer and more flexible and can be used for plumbing, electrical cables, and flooring. Because PVC is lightweight, durable, and easy to work with, it’s replacing traditional materials like wood, metal, concrete, rubber, and ceramics in many different applications.

LDPE (Group 4): LDPE stands for Low-Density Polyethylene. It’s different from HDPE because its molecules are less dense, which makes it thinner and more flexible. LDPE has a simple structure, making it easy and inexpensive. It’s commonly used for plastic bags, six-pack rings, containers, dispensing bottles, and plastic wraps.

PP (Group 5): PP, or Polypropylene, is the second most widely produced plastic worldwide, and its use is expected to increase. It’s challenging and robust, can handle high temperatures, and is used in products like Tupperware, car parts, thermal vests, yogurt containers, and disposable diapers. Fun fact: PP is incredibly resistant to wear and tear, which makes it perfect for “living hinges"—these are the thin parts of plastic that let something bend or fold, like on a flip-top lid.

PS (Group 6): Polystyrene is the sixth type of plastic. It can be solid or foamy. It’s cheap to make and can be found in many things like beverage cups, insulation, packing materials, egg cartons, and disposable plates and cups. You might know it by its brand name, Styrofoam. Styrofoam is highly flammable and can release harmful chemicals, especially when heated (when people microwave food in take-out containers). Environmentally, it’s one of the worst plastics. First, it breaks down slowly. Second, polystyrene foam can blow away in the wind and float on water because it’s so light. Animals sometimes mistake it for food, which can hurt birds or sea creatures if they eat it.

Other Plastic (Group 7): Group 7 includes plastics that don’t fit into the other six types. Polycarbonate (PC) is a common type that makes solid and rigid products like sunglasses, goggles, mobile phones, and CDs. However, there’s controversy because polycarbonates can release a chemical called bisphenol A (BPA) when heated, which is considered harmful to the environment. Also, plastics in group 7 are hardly ever recycled.

*Make a chart of the seven basic types of plastic and put the names of the plastics inside a recycling triangle to communicate the need to recycle these non-biodegradable products! *

Go on a plastic treasure hunt. Start looking room by room. Make a list of everything in your house that is plastic. Be sure you look at the floor, the walls, and the window for starters. Many electrical outlet covers are plastic. The covering of electrical cords is a form of soft plastic. Recessed lights in the ceiling often have plastic parts. Lamps and lampshades can be plastic, too. Do you have any plastic furniture? Could you look at your possessions? You may have dishes, cups, appliances, and toys that are made of plastic. How about plastic pens and markers? Combs, brushes, and glasses are often plastic. Do you have plastic purses, bags, or shoes? Do you hang clothes in your closet on plastic hangers? Do you have plastic toys around your house? Which rooms in your home contain the most plastic? Collect plastic things in your house, take a photo, and upload your plastic collection to the gallery for activity 2.

People used to be optimistic about plastics, thinking they were great for everything. But after World War II, Americans started to see them differently. They weren’t always seen as good anymore. In the 1960s, people noticed plastic trash in the oceans for the first time. During that decade, Americans started realizing more about environmental problems. Rachel Carson’s book “Silent Spring” 1962 showed how dangerous pesticides could be. Then, in 1969, there was a big oil spill off California, and the Cuyahoga River in Ohio caught on fire because it was so polluted. These events made people worry more about pollution. As they learned more about these issues, they began to see that plastic waste sticking around was a big problem.

Research Plastic Problems in your waterways and make a poster sharing what you learned.

Most of the plastic we throw away doesn’t get recycled or reused—only about 20% does. The rest, about 80%, ends up either buried or in the ocean. There are two main ways that plastic breaks down: photo-degradation and biodegradation. Photo-degradation happens when plastic is exposed to sunlight. The only plastic that ends up in the ocean gets exposed to sunlight, not the plastic buried underground. Buried plastic can only break down through biodegradation, where bacteria or fungi from micro-organisms help break it down. However, the strong bonds in plastic make it hard for these organisms to break apart. That means buried plastic might not break down for hundreds of years or even longer!

Look at the Lifecycle of Plastics and make a timeline of everyday plastics and how long it will take for them to decompose. You will be shocked!!

Recycling plastic is a powerful way to protect our environment. Plastic, as we know, takes a very long time to break down naturally. But through recycling, we can give it a new life. The process is fascinating. Machines automatically sort the plastic, and then workers manually check to ensure no unwanted materials are mixed in. After sorting and cleaning, the plastic can be shredded into small pieces called flakes or melted down to make pellets. These pellets are then used to mold new products out of recycled plastic. It’s a beautiful cycle of conservation and renewal. Please take a look at the steps to recycling.

Collection: How plastic is collected for recycling depends on how businesses, restaurants, and people throw away their plastic. If plastic ends up in regular trash, it can’t be recycled, so it’s important to separate plastic waste from other trash.

Sorting: At recycling centers, machines sort the collected plastic based on its type, color, and how it was made. Each type of plastic needs to be sorted because they’re recycled differently. Most recycling places can only handle one kind of plastic at a time.

Washing: The sorted plastic is washed to clean off labels and sticky stuff. This makes the plastic better for creating new things. The final product might only be strong if it’s cleaned well.

Shredding or Resizing: After washing, the plastic is shredded into small pieces or pellets using machines. Smaller pieces are easier to handle and can be reshaped into new products. Machines also remove any metal left in the plastic.

Melting: The shredded plastic pieces are dried and then melted down using special equipment. The melted plastic can be molded into different shapes or turned into pellets to make new products.

Identification and Classification: The melted plastic is tested to check its quality. One test checks how dense the plastic is by putting it in water—denser plastic sinks. Another test measures the size of the plastic particles by using air. These tests ensure that the plastic is suitable for recycling.

Compounding or Extruding: Finally, the melted plastic is turned into pellets. These pellets can be used later to make new plastic products. This process helps recycle plastic so it can be used again instead of being thrown away.

Plastics have revolutionized our world, powering the creation of essential technologies such as computers, cell phones, and life-saving medical treatments. Their lightweight and insulating properties have not only conserved fossil fuels but also made products more affordable and accessible. However, recognizing the environmental impact, innovative industries are now reshaping plastics for a more sustainable future. Scientists are developing bioplastics derived from plants, offering a promising eco-friendly alternative to traditional petroleum-based plastics. Additionally, research efforts are focused on creating biodegradable plastics and improving recycling methods, with some even exploring the conversion of used plastics back into fuel. These advancements promise to redefine the role of plastics in building a greener and more sustainable planet.

Research Innovative industries that are reshaping plastic for a more sustainable planet.