The exact number is unclear. Plastic is not only one of the ingredients that made the same way every time. Although the plastic can be broken down into broad types or categories, there are actually thousands of different plastics, each with its own composition and characteristics. One plastic can block the oxygen to reach the food. Other possible but difficult transparent as glass. Or stretch and get back in shape.
That's why plastic is used in many ways: they protect our food, protect our homes, improve our cars gas mileage, keep us dry when it rains ... and many other things.
Plastic is the result of a mixture of chemical and engineering. As innovation marches, scientists and engineers can make new plastic to do more and more things.
So even though the amount is not clear plastic, plastic makers tend plastic into two general groups of classes: thermoplastics and thermosets.
Thermoplastics can be re-melted and basically back to their original state as a way kind of ice can melt and then cooled again. Thermoplastics are usually produced first in a separate process to make small pellets; This pellet is then heated and molded to make all kinds of consumer and industrial products. Thermoplastic including plastic you may be familiar with: polyethylene, polypropylene, polyvinyl chloride, polystyrene, nylon, polycarbonate, and others.
Thermosets are usually produced and formed into a product at the same time-and they can not return to their home countries. They are generally formed using heat and be "set," such as eggs cooked. Thermoset including vulcanized synthetic rubber, acrylic, polyurethane, melamine, silicone, epoxies, and others.
There is another category of plastics:
Engineering plastic ... Has good mechanical properties have been improved and engineered often greater durability. For example, impact-resistant polycarbonate. Polyamides such as nylon against abrasion. Some combination of plastic, such as ABS is very difficult (acrylonitrile butadiene styrene). List of engineering plastics long enough.
Plastic fibers precisely that: a plastic that has been spun into fibers or filaments which are used to make cloth, rope, ropes, fiber optic cable and even body armor. Most plastic fiber is strong, elastic, and stable under heat (so that the fabric can be ironed). Some of the most known plastic fibers are polyester, nylon, rayon, acrylic, and spandex, although there are many more. (Note: sometimes called polyethylene terephthalate polyester-it is also used to make plastic water bottle which can then be recycled into fibers for clothing, such as fleece jackets and t-shirts).
There are many more categories, such as coatings, adhesives, elastomers and rubber, which includes the plastic used in everything from outside the shuttle to food packaging.
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