The difference between polymer and plastic is complicated as all plastics are polymers but not all polymers are plastic. Many companies and universities agree that polymer alone is essentially useless, and it must be combined with other mediums to form a usable product. However, recognizing that both polymer and plastic are two separate products is important even though one requires the other for creation.

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Many common household items now contain plastic.

Polymer

Very few, if any, true polymer products are available on the market. In fact, when marketing products, polymer and plastic can be used interchangeably. According to Dr. Ahmed Lofti, polymers are long chains of molecules that can be either biological or inorganic, thus lending the term 'polymer' to many different items. Examples of items containing polymer include Bakelite, the synthetic fiber known as rayon, tar, shellac and the tree saps that are used to produce latex.

Plastic

While polymer can be either biological or inorganic, plastic cannot. Plastic is a purely synthetic, man-made material, but it does often incorporate polymer into its composition. It gets its name from the Greek words "plastikos" and "plastos," meaning "fit for molding" and "molded." The most commonly known types of plastic are polyethylene terephthalate (PET), vinyl, PVC, polypropylene and polycarbonates like bisphenol A, better known as BPA.

Pros and Cons of Polymer

Some polymer products can be recycled whereas some cannot. For example, thermoplastic polymers are polymers that can be reheated and reformed again and again. Meanwhile, thermoset polymers cannot be reheated or reformed, making them useless for recycling. However, polymer tends to be more flexible in terms of what it can be used for: clothing, textiles and plastic products. It can be manipulated into many forms: fibers, sheets, cords and various shapes.

Pros and Cons of Plastic

Since plastic is partially comprised of polymers, the two share many of the same characteristics. Some plastics can be recycled while others cannot. Some plastics are flexible and can be used in items like textiles or clothing while other plastics cannot and may be more suited toward use for items like plastic storage containers or a computer mouse. However, like polymer, plastic can be used in a wide variety of items.