Plastic: from A to Z

Bioplastic

This highly flexible term is currently used for a range of plastics, including both fossil-fuel and biologically derived plastics that are biodegradable, and bio-based plastics that are not biodegradable. In other words, there is no guarantee that a “bioplastic” will be made from non-toxic, non-fossil fuels or that it will biodegrade.

biodegradable plastic

A biodegradable product must, with the help of microorganisms, decompose into natural raw materials over a certain period of time. “Biodegradation” is a deeper process than “destruction” or “decay”. When they say that plastic “breaks down”, in reality it just becomes smaller pieces of plastic. There is no generally accepted standard for labeling a product as “biodegradable”, which means there is no clear way to define what it means, and therefore manufacturers apply it inconsistently.

supplements

Chemicals added during the manufacture of plastic products to make them stronger, safer, more flexible, and a number of other desirable characteristics. Common additives include water repellants, flame retardants, thickeners, softeners, pigments, and UV curing agents. Some of these additives may contain potentially toxic substances.

Compostable plastic

For an item to be compostable, it must be able to decompose into its natural elements (or biodegradable) in a “reasonable composting environment”. Some plastics are compostable, although most cannot be composted in a regular backyard compost pile. Instead, they require a much higher temperature over a period of time to fully decompose.

Microplastics

Microplastics are plastic particles that are less than five millimeters long. There are two types of microplastics: primary and secondary.

Primary microplastics include resin pellets that are melted down to make plastic products and microbeads added to products such as cosmetics, soaps and toothpaste as abrasives. Secondary microplastics result from the crushing of large plastic products. Microfibers are individual plastic strands that are woven together to make fabrics such as polyester, nylon, acrylic, etc. When worn and washed, microfibers get into the air and water.

Single stream processing

A system in which all recyclable materials – newspapers, cardboard, plastic, metal, glass – are placed in one recycling bin. Secondary waste is sorted at the recycling center by machines and by hand, not by homeowners. This approach has pros and cons. Proponents say single-stream recycling increases public participation in recycling, but opponents say it leads to more pollution because some of the recyclable material ends up in landfills and is more costly.

Disposable plastics

Plastic products meant to be used only once, such as thin grocery bags and film packaging that seal everything from food to toys. About 40% of all non-fiber plastics are used for packaging. Environmentalists are trying to convince people to cut back on single-use plastics and instead opt for more durable multi-use items like metal bottles or cotton bags.

oceanic circular currents

There are five major circular currents on Earth, which are large systems of rotating ocean currents created by winds and tides: the North and South Pacific Circular Currents, the North and South Atlantic Circular Currents, and the Indian Ocean Circular Current. Circular currents collect and concentrate marine debris into large areas of debris. All major gyres now have patches of debris, and new patches are often found in smaller gyres.

ocean trash patches

Due to the action of ocean currents, marine debris often collects in oceanic circular currents, forming what are known as debris patches. In the largest circular currents, these patches can cover a million square miles. Most of the material that makes up these spots is plastic. One of the largest concentrations of marine debris is called the Great Pacific Garbage Patch and is located between California and Hawaii in the North Pacific Ocean.

Polymers

Plastics, also called polymers, are made by joining together small blocks or unit cells. Those blocks that chemists call monomers are made up of groups of atoms derived from natural products or by synthesizing primary chemicals from oil, natural gas, or coal. For some plastics, such as polyethylene, only one carbon atom and two hydrogen atoms can be a repeat unit. For other plastics, such as nylon, the repeat unit may include 38 or more atoms. Once assembled, monomer chains are strong, light and durable, which makes them so useful in the home – and so problematic when they are carelessly disposed of.

PAT

PET, or polyethylene terephthalate, is one of the most widely used types of polymers or plastics. It is a transparent, durable and lightweight plastic belonging to the polyester family. It is used to make common household items.

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