How are plastic bags made? That's a question most of us probably didn't think about until we realized how detrimental plastic bags are to the environment, but understanding the process can help inspire us to start recycling and find alternatives to these bags.
From Parkesine To Plastic
Cheap plastic bags and plastic shopping bags are made in much the same way that thermoplastics were made in 1856, when Alexander Parkes invented the first plastic, called Parkesine. Back then Parkes was creating plastics for use as building materials, but Parkesine was prone to cracking, expensive to produce and highly flammable, so it didn't catch on as he would have liked.
The Development Of Polyethylene
The cheap plastic bags found in grocery stores, as well as most other plastic bags and other plastic items, are made from basically two major ingredients: petroleum and natural gas, which are then separated and converted into different types of polymers. Polymers, which are filled with large molecules called monomers, are repeating units. These repeating units are used in a variety of ways to make ethylene. When ethylene is processed, it forms molecular chains. These chains create a chemical called polyethylene.
Plastic bags are just one of the many products that can be made from polyethylene. Plastic bags are made from three types of polyethylene: high-density polyethylene (HDPE), low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE). HDPE and LDPE plastics are created by a process called Ziegler-Natta vinyl polymerization, named after the two men who created the process and won a Nobel Prize for their efforts. Unfortunately, carcinogens are released into the atmosphere when ethylene and polyethylene are created. These carcinogens are dangerous to humans and animals who breathe the toxic air.