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What Are Plastics

One Word: Plastics

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PP Plastic Bottle Caps

PP Plastic Bottle Caps

Tobyotter via Flickr (Creative Commons)

Plastics Used Everyday

Every day, people use plastics in various applications. Over the last 50 to 60 years, the uses for plastic have expanded to infiltrate virtually every aspect of life. Because of how versatile the material is, and how affordable it can be, it has taken the place of other products including wood and metals.

The properties of the various types of plastics make it beneficial for manufacturers to use. Consumers like it because it is easy to use, lightweight and easy to maintains.

Types of Plastics

Overall, there are about 45 unique types of plastics and each type has dozens of different variations. Manufacturers can change the physical structure just slightly to benefit the application for which they are using it. When manufacturers change or modify things like the molecular weight distribution, the density or the melt indices, they alter the effectiveness and create plastics with many specific properties - and therefore many different uses.

Two Plastic Categories

There are two main types of plastics, thermoset plastics and thermoplastics. Breaking these down further, you can see the everyday uses of each type. With thermoset plastics, the plastic will hold its shape long term once it has cooled to room temperature and hardened thoroughly.

This type of plastic cannot return to its original form - it cannot be melted down into its original form. Epoxy resins and polyurethanes are some examples of this type of thermosetting plastic. It is commonly used in tires, auto parts, and composites.

The second category is thermoplastics. Here, you have more flexibility and versatility. Because it will return to its original form when heated, these plastics are commonly used in various applications. They can be made into films, fibers, and other forms.

Specific Types of Plastics

Below are some of the specific types of plastics and how they are in use today. Consider their chemical properties and benefits, too:

PET or Polyethylene terephthalate - This plastic is ideal for food storage and water bottles. It is commonly used for things like storage bags, too. It does not leach into the food, but is sturdy and can be drawn into fibers or films.

PVC or Polyvinyl Chloride - It is brittle but stabilizers are added to it. This makes it a softer plastic that's easy to mold into various shapes. It is commonly used in plumbing applications because of its durability.

Polystyrene - Commonly known as Styrofoam, it is one of the less ideal options today for environmental reasons. However, it is very lightweight, easy to mold and it works as an insulator. That is why it is heavily used in furniture, cabinetry, glasses and other impact-resistant surfaces. It is also commonly added with a blowing agent to create foam insulation.

Polyvinylidine Chloride (PVC) - Commonly known as Saran, this plastic is used in wraps to cover food. It is impermeable to odors from food, and can be drawn into various films.

Polytetrafluoroethylene - A growing popular choice is this plastic also known as Teflon. First manufactured by DuPont in 1938, it is a heat-resistant form of plastic. It is very stable and strong, and is unlikely to be damaged by chemicals. Moreover, it creates a surface that is almost frictionless. This is why it is used in various cookware (nothing sticks to it) and in tubing, plumbing tapes and in waterproof coating products.

Polypropylene - Commonly called just PP, this plastic has various forms. However, it has uses in many applications including tubes, car trims, and bags.

Polyethylene - Also known as HDPE or LDPE, it is one of the most common forms of plastics. New formations of it make it possible for this plastic to be flat. Its initial uses were for electrical wires but it is now found in many disposable products, including gloves and garbage bags. It is also used in other film applications such as wraps, as well as in bottles.

The use of plastics every day is more commonplace than many might think. By making small changes to these chemicals, new and versatile solutions are obtained.

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