WEBVTT - How do plastics work? What is actually in a plastic?

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<v Speaker 1>Welcome to Brainstuff from house stuff works dot com where

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<v Speaker 1>smart happens. Hi. I'm braining with today's question, how do

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<v Speaker 1>plastics work and what is actually in a plastic? What's

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<v Speaker 1>it made out of? If you were to crawl under

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<v Speaker 1>your house and poke around, chances are that you would

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<v Speaker 1>find quite a bit of a white plastic pipe. This

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<v Speaker 1>pipe is made of a very common, long lasting, strong

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<v Speaker 1>plastic called PVC or polyvinyl chloride PBC. Plastic can be

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<v Speaker 1>found in lots of other places around the home, including

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<v Speaker 1>vinyl siding and vinyl windows. Then there's the fake leather

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<v Speaker 1>made of vinyl, found in everything from furniture to jackets,

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<v Speaker 1>to shoes, and many toys are made of vinyl as well.

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<v Speaker 1>And that is just one kind of plastic. Polyethylene is

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<v Speaker 1>even more popular. You find polyethylene and everything from plastic

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<v Speaker 1>container is two plastic bags, from garbage cans to garbage bags.

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<v Speaker 1>You can even make bulletproof protection out of it if

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<v Speaker 1>you make it thick enough. There are many other types

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<v Speaker 1>of plastics in common use. There's pet plastic, for example,

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<v Speaker 1>founding clear plastic bottles for soda, as well as carpet

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<v Speaker 1>and clothing abs. Plastic makes everything from pipes to lego bricks.

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<v Speaker 1>Polystyrene makes styrofoam as well as plastic forks and containers.

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<v Speaker 1>The bottom line is that we find these different plastics

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<v Speaker 1>everywhere we look, in almost any product we touch on

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<v Speaker 1>a daily basis. To understand how useful plastic is, think

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<v Speaker 1>about where we would be if plastic had never been discovered.

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<v Speaker 1>Let's say you want a container for some shampoo. If

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<v Speaker 1>there's no plastic, what do you use to make the container?

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<v Speaker 1>There's wood, paper, pottery, glass, fabric, and metal. You can

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<v Speaker 1>make the container out of glass, but what if you

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<v Speaker 1>drop it? Or what about a computer keyboard? You can

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<v Speaker 1>make it out of metal, but now it's a lot

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<v Speaker 1>heavier and more expensive. Plastics are obviously handy, they're inexpensive, lightweight,

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<v Speaker 1>and strong. Where do they come from and what makes

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<v Speaker 1>them so popular? Let's start with polyethylene, since it is

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<v Speaker 1>both the most common plastic as well as the simplest.

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<v Speaker 1>A plastic like polyethylene starts with crude oil. If you

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<v Speaker 1>look at crude oil, it contains chains of carbon atoms

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<v Speaker 1>decorated with hydrogen atoms. Polyethylene begins with an ethylene molecule

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<v Speaker 1>derived from crude oil. And this molecule contains two carbon

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<v Speaker 1>atoms and four hydrogen atoms. To make polyethylene, chemists have

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<v Speaker 1>to link these ethylene molecules together into long chains that

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<v Speaker 1>are hundreds of units long. That's where the name polyethylene

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<v Speaker 1>comes from. Your chaining together these ethylene molecules to make

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<v Speaker 1>incredibly long chains. The long chains then knit together to

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<v Speaker 1>create a strong, flexible plastic. If you think about it,

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<v Speaker 1>polyethylene plastic is really nothing more than solidified gasoline. It

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<v Speaker 1>contains exactly the same atoms, just slightly rearranged and organized

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<v Speaker 1>into much longer chains. Therefore, polyethylene is going to cost

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<v Speaker 1>about the same as gasoline by the pound, and it's

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<v Speaker 1>also going to burn like gasoline. There's even a company

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<v Speaker 1>that makes a machine to turn plastic bags back into

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<v Speaker 1>liquid oil to be reused. PVC is very similar to polyethylene,

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<v Speaker 1>except one of the hydrogen atoms is replaced by a

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<v Speaker 1>chlorine atom. About half of the weight of PVC comes

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<v Speaker 1>from chlorine, so you need less oil to make PVC,

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<v Speaker 1>and that chlorine atom also adds some concerns when PVC

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<v Speaker 1>gets thrown out. When PVC is incinerated, it produces dioxins,

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<v Speaker 1>which are good for neither animals nor people. Some countries

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<v Speaker 1>are therefore working to phase out PVC, either altogether or

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<v Speaker 1>in certain kinds of products. The environmental problem is the

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<v Speaker 1>only real down side to most plastics. One of the

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<v Speaker 1>things that makes plastics so appealing is that they're strong

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<v Speaker 1>and long lasting. But if plastics escape into the environment,

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<v Speaker 1>those assets become liabilities. The plastics can last for centuries,

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<v Speaker 1>and they are accumulating in the Pacific and the Atlantic

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<v Speaker 1>oceans in areas called garbage patches. While the patches grow,

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<v Speaker 1>there's no real proposed solution to eliminating them. The best

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<v Speaker 1>defense against plastic pollution is collection and recycling. If labeled

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<v Speaker 1>with a recycling symbol, it's easy to tell what kind

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<v Speaker 1>of plastic you're holding in your hand. The symbol one

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<v Speaker 1>or the letter's PET denote pet plastic. HDPE or two

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<v Speaker 1>is high density polyethylene PVC, or three is polyvinyl chloride

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<v Speaker 1>l DPE or four is low density polyethylene pp or

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<v Speaker 1>five is polypropylene ps or six is polystyrene, and seven

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<v Speaker 1>stands for everything else. The next time you pick up

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<v Speaker 1>or touch a piece of plastic, which will probably be

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<v Speaker 1>about three seconds from now, keep in mind what you're holding.

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<v Speaker 1>It's a piece of solidified crude oil molded into the

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<v Speaker 1>object you need. Be sure to check out our new

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