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Plastic bag

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A plastic bag, also known as a poly bag or pouch, is a versatile container made from thin, flexible materials. These materials include plastic film, nonwoven fabrics, or plastic textiles.

Hemdchentuete
Hemdchentuete

Because they are lightweight and strong, they are used for transporting many goods. This includes foods, produce, powders, ice, and magazines. They are also used for more specialized items like chemicals or medical waste. Plastic bags are a common form of packaging used globally in many different ways.

Most modern plastic bags are created through a process called heat sealing. In this method, heat is used to join the seams of the plastic together.

Handle in plastic bag
Handle in plastic bag

Some bags are instead bonded using adhesives or are stitched together. There are many different designs available depending on what the bag needs to do. For example, some bags feature gussets, which are folds that allow the bag to hold a higher volume. Other designs include stand-up pouches that can sit upright on a shelf or in a refrigerator.

Stand-up pouch
Stand-up pouch

Some bags even include reclosable press-to-seal zipper strips for easy opening and closing.

There are many specialized types of plastic bags used for specific tasks. In the medical field, non-porous plastic film is used to isolate infectious body fluids.

They have bags of milk too! (6192608782)
They have bags of milk too! (6192608782)

Other porous bags made from nonwoven plastics can be sterilized with gas to maintain sterility for patients. For cooking, boil-in-bags made of tough nylon or polyester can withstand the heat of boiling water. Some of these are perforated to allow hot water to reach foods like rice or noodles. On an industrial scale, Flexible Intermediate Bulk Containers, or FIBCs, are used.

Big bag
Big bag

These large "bulk bags" are made of heavy-duty woven plastic fibers and can carry between 500 kg and 2,000 kg.

The history of the modern plastic bag began in Sweden. In the late 1950s, Curt Lindquist, the CEO of the Celloplast company, began experimenting with plastic. However, the modern lightweight shopping bag was specifically developed by an engineer named Sten Gustaf Thulin. In the early 1960s, Thulin created a method to form a one-piece bag. He did this by folding, welding, and die-cutting a flat tube of plastic. This design was strong and could carry a high load. Celloplast was awarded the patent for this invention in 1965. By the mid-1980s, these bags became a standard way to carry groceries in the developed world.

Global usage of plastic bags is massive and varies by country. Every year, an estimated 1 to 5 trillion plastic bags are used and discarded worldwide. The lifespan of a bag, from the store to its destination, is often only 12 minutes. In 2014, people in the United States used approximately 320 bags per capita. Usage rates differ greatly across the globe. For instance, the average consumer in China uses only two or three bags per year. In contrast, people in Poland, Hungary, and Slovakia use more than 400 bags annually.

Plastic bags present significant environmental challenges because they do not biodegrade. Instead, they undergo photodegradation. This is a process where light breaks the plastic down into smaller, toxic pieces.

Biodegradable bag
Biodegradable bag

Most bags are made from petroleum products and natural gas. About 8% of the world's petroleum resources are used to create plastic bags. If disposed of improperly, bags can enter the ocean and harm wildlife. In the Atlantic Ocean alone, an estimated 300 million bags end up in the water. Floating bags can look like jellyfish, which may cause sea turtles to eat them by mistake. This ingestion can lead to premature death for the animal.

Because of these impacts, many governments are taking action. Many cities and countries have introduced legislation to phase out lightweight plastic bags. For example, India has banned bags thinner than 50 microns. In the United States, California passed a law in 2014 to ban their use, though a later law in 2024 aims to close previous loopholes. Despite these concerns, some studies suggest plastic bags have certain advantages. They often use less material than boxes or glass jars. In 2009, Germany's Institute for Energy and Environmental Research found that oil-based plastics could have a better life-cycle analysis than bioplastics if they are recycled.

Different meat products of Thailand
Different meat products of Thailand

This is due to the specific processes used in raw-material production.

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🖼️ Images & Media (7)
File:Handle in plastic bag.jpg
Handle in plastic bag.jpg
File:Stand-up pouch.jpg
Stand-up pouch.jpg
File:Big bag.jpg
Big bag.jpg
File:Hemdchentuete.jpg
Hemdchentuete.jpg
File:They have bags of milk too! (6192608782).jpg
They have bags of milk too! (6192608782).jpg
File:Different meat products of Thailand.JPG
Different meat products of Thailand.JPG
File:Biodegradable bag.jpg
Biodegradable bag.jpg
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