Crude oil is not just a resources for fuel. Some parts of crude oil are used as raw materials to make polymers, such as plastic.
What Are Polymers? A polymer is a compound substance made up of chains of molecules. There are some natural polymers, such as the sap from rubber trees that are used to make tires. Most polymers are artificial. They are made from crude oil. Different kinds of artificial polymers can be made to have different properties. Some are rough solids, such as the nylon fiber used to make bullet-proof armor. Others, such as acrylic paint, are liquid.
Uses of Plastics..Plastic...the most familiar type of polymer...are very useful, because they are waterproof, can be transparent, or any color ot texture, and can be molded using heat into most different uses.
Plastics can be used to make artificial joints, like the hip jpint, because it is strong yet light, can be accurately shaped and stuck to bone.
PVC is flexible and used to make plastic bags, garden furniture and water pipes.
Tougher PETE is used to make soda and motor oil bottles, and light, s oft polystyrene is molded into packing materials to protect goods from damage.
Plastic reinfoeced with fine strands of carbon is used for objects that need to be flexible and withstand enormous stresses, such as helicopter blades or tennis rackets.
Sticking Around. Another quality that makes plastic useful is that it does not rot or biodegrade. This is also what makes plastic a problem.
Plastic bags can take up to 500 years to decay in landfill sites.
Many types of plastics can be recyled to make different plastics products. But most countries find it quicker, and cheaper, to burn plastic in waste incinerators. This releases polluting gases, such as dioxins, into the atmosphere.
In Japan, where over 70 percent of waste is burned, people who live near incinerators have more cancers as a result of breathing in dioxins.
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