1 00:00:00,520 --> 00:00:03,840 Speaker 1: Welcome to Brainstuff from house stuff works dot com where 2 00:00:03,840 --> 00:00:14,960 Speaker 1: smart happens. Hi. I'm braining with today's question, how do 3 00:00:15,240 --> 00:00:18,720 Speaker 1: plastics work and what is actually in a plastic? What's 4 00:00:18,720 --> 00:00:21,560 Speaker 1: it made out of? If you were to crawl under 5 00:00:21,600 --> 00:00:24,200 Speaker 1: your house and poke around, chances are that you would 6 00:00:24,200 --> 00:00:27,680 Speaker 1: find quite a bit of a white plastic pipe. This 7 00:00:27,760 --> 00:00:31,120 Speaker 1: pipe is made of a very common, long lasting, strong 8 00:00:31,280 --> 00:00:36,680 Speaker 1: plastic called PVC or polyvinyl chloride PBC. Plastic can be 9 00:00:36,720 --> 00:00:39,960 Speaker 1: found in lots of other places around the home, including 10 00:00:40,080 --> 00:00:43,800 Speaker 1: vinyl siding and vinyl windows. Then there's the fake leather 11 00:00:44,360 --> 00:00:47,880 Speaker 1: made of vinyl, found in everything from furniture to jackets, 12 00:00:47,880 --> 00:00:51,080 Speaker 1: to shoes, and many toys are made of vinyl as well. 13 00:00:51,680 --> 00:00:55,120 Speaker 1: And that is just one kind of plastic. Polyethylene is 14 00:00:55,160 --> 00:00:59,360 Speaker 1: even more popular. You find polyethylene and everything from plastic 15 00:00:59,400 --> 00:01:03,120 Speaker 1: container is two plastic bags, from garbage cans to garbage bags. 16 00:01:03,480 --> 00:01:06,160 Speaker 1: You can even make bulletproof protection out of it if 17 00:01:06,200 --> 00:01:09,119 Speaker 1: you make it thick enough. There are many other types 18 00:01:09,160 --> 00:01:13,319 Speaker 1: of plastics in common use. There's pet plastic, for example, 19 00:01:13,800 --> 00:01:17,160 Speaker 1: founding clear plastic bottles for soda, as well as carpet 20 00:01:17,240 --> 00:01:22,040 Speaker 1: and clothing abs. Plastic makes everything from pipes to lego bricks. 21 00:01:22,360 --> 00:01:26,760 Speaker 1: Polystyrene makes styrofoam as well as plastic forks and containers. 22 00:01:27,280 --> 00:01:30,320 Speaker 1: The bottom line is that we find these different plastics 23 00:01:30,360 --> 00:01:33,280 Speaker 1: everywhere we look, in almost any product we touch on 24 00:01:33,319 --> 00:01:37,760 Speaker 1: a daily basis. To understand how useful plastic is, think 25 00:01:37,760 --> 00:01:40,959 Speaker 1: about where we would be if plastic had never been discovered. 26 00:01:41,319 --> 00:01:44,800 Speaker 1: Let's say you want a container for some shampoo. If 27 00:01:44,840 --> 00:01:48,200 Speaker 1: there's no plastic, what do you use to make the container? 28 00:01:48,240 --> 00:01:52,600 Speaker 1: There's wood, paper, pottery, glass, fabric, and metal. You can 29 00:01:52,720 --> 00:01:54,720 Speaker 1: make the container out of glass, but what if you 30 00:01:54,800 --> 00:01:57,880 Speaker 1: drop it? Or what about a computer keyboard? You can 31 00:01:57,920 --> 00:01:59,920 Speaker 1: make it out of metal, but now it's a lot 32 00:02:00,240 --> 00:02:05,840 Speaker 1: heavier and more expensive. Plastics are obviously handy, they're inexpensive, lightweight, 33 00:02:05,880 --> 00:02:08,400 Speaker 1: and strong. Where do they come from and what makes 34 00:02:08,480 --> 00:02:12,720 Speaker 1: them so popular? Let's start with polyethylene, since it is 35 00:02:12,760 --> 00:02:15,920 Speaker 1: both the most common plastic as well as the simplest. 36 00:02:16,320 --> 00:02:20,280 Speaker 1: A plastic like polyethylene starts with crude oil. If you 37 00:02:20,320 --> 00:02:23,720 Speaker 1: look at crude oil, it contains chains of carbon atoms 38 00:02:23,800 --> 00:02:29,480 Speaker 1: decorated with hydrogen atoms. Polyethylene begins with an ethylene molecule 39 00:02:29,639 --> 00:02:33,560 Speaker 1: derived from crude oil. And this molecule contains two carbon 40 00:02:33,639 --> 00:02:38,440 Speaker 1: atoms and four hydrogen atoms. To make polyethylene, chemists have 41 00:02:38,639 --> 00:02:42,680 Speaker 1: to link these ethylene molecules together into long chains that 42 00:02:42,720 --> 00:02:46,519 Speaker 1: are hundreds of units long. That's where the name polyethylene 43 00:02:46,520 --> 00:02:51,000 Speaker 1: comes from. Your chaining together these ethylene molecules to make 44 00:02:51,080 --> 00:02:55,200 Speaker 1: incredibly long chains. The long chains then knit together to 45 00:02:55,280 --> 00:02:58,960 Speaker 1: create a strong, flexible plastic. If you think about it, 46 00:02:59,160 --> 00:03:04,160 Speaker 1: polyethylene plastic is really nothing more than solidified gasoline. It 47 00:03:04,240 --> 00:03:08,560 Speaker 1: contains exactly the same atoms, just slightly rearranged and organized 48 00:03:08,600 --> 00:03:12,600 Speaker 1: into much longer chains. Therefore, polyethylene is going to cost 49 00:03:12,639 --> 00:03:15,440 Speaker 1: about the same as gasoline by the pound, and it's 50 00:03:15,480 --> 00:03:18,920 Speaker 1: also going to burn like gasoline. There's even a company 51 00:03:18,960 --> 00:03:22,120 Speaker 1: that makes a machine to turn plastic bags back into 52 00:03:22,160 --> 00:03:27,800 Speaker 1: liquid oil to be reused. PVC is very similar to polyethylene, 53 00:03:27,919 --> 00:03:31,079 Speaker 1: except one of the hydrogen atoms is replaced by a 54 00:03:31,160 --> 00:03:34,880 Speaker 1: chlorine atom. About half of the weight of PVC comes 55 00:03:34,920 --> 00:03:38,160 Speaker 1: from chlorine, so you need less oil to make PVC, 56 00:03:38,560 --> 00:03:42,360 Speaker 1: and that chlorine atom also adds some concerns when PVC 57 00:03:42,520 --> 00:03:47,200 Speaker 1: gets thrown out. When PVC is incinerated, it produces dioxins, 58 00:03:47,320 --> 00:03:51,120 Speaker 1: which are good for neither animals nor people. Some countries 59 00:03:51,160 --> 00:03:55,200 Speaker 1: are therefore working to phase out PVC, either altogether or 60 00:03:55,240 --> 00:03:59,000 Speaker 1: in certain kinds of products. The environmental problem is the 61 00:03:59,040 --> 00:04:02,040 Speaker 1: only real down side to most plastics. One of the 62 00:04:02,120 --> 00:04:05,400 Speaker 1: things that makes plastics so appealing is that they're strong 63 00:04:05,480 --> 00:04:09,240 Speaker 1: and long lasting. But if plastics escape into the environment, 64 00:04:09,320 --> 00:04:14,200 Speaker 1: those assets become liabilities. The plastics can last for centuries, 65 00:04:14,280 --> 00:04:17,240 Speaker 1: and they are accumulating in the Pacific and the Atlantic 66 00:04:17,240 --> 00:04:21,279 Speaker 1: oceans in areas called garbage patches. While the patches grow, 67 00:04:21,640 --> 00:04:25,559 Speaker 1: there's no real proposed solution to eliminating them. The best 68 00:04:25,600 --> 00:04:30,520 Speaker 1: defense against plastic pollution is collection and recycling. If labeled 69 00:04:30,520 --> 00:04:33,520 Speaker 1: with a recycling symbol, it's easy to tell what kind 70 00:04:33,560 --> 00:04:36,760 Speaker 1: of plastic you're holding in your hand. The symbol one 71 00:04:36,920 --> 00:04:41,559 Speaker 1: or the letter's PET denote pet plastic. HDPE or two 72 00:04:41,680 --> 00:04:46,520 Speaker 1: is high density polyethylene PVC, or three is polyvinyl chloride 73 00:04:47,000 --> 00:04:51,160 Speaker 1: l DPE or four is low density polyethylene pp or 74 00:04:51,279 --> 00:04:56,200 Speaker 1: five is polypropylene ps or six is polystyrene, and seven 75 00:04:56,279 --> 00:04:59,320 Speaker 1: stands for everything else. The next time you pick up 76 00:04:59,440 --> 00:05:01,760 Speaker 1: or touch a piece of plastic, which will probably be 77 00:05:01,800 --> 00:05:05,239 Speaker 1: about three seconds from now, keep in mind what you're holding. 78 00:05:05,680 --> 00:05:09,200 Speaker 1: It's a piece of solidified crude oil molded into the 79 00:05:09,240 --> 00:05:13,480 Speaker 1: object you need. Be sure to check out our new 80 00:05:13,560 --> 00:05:16,880 Speaker 1: video podcast, Stuff from the Future. Join how Stuff Work 81 00:05:16,960 --> 00:05:20,520 Speaker 1: staff as we explore the most promising and perplexing possibilities 82 00:05:20,560 --> 00:05:24,679 Speaker 1: of tomorrow. The House Stuff Works iPhone app has arrived. 83 00:05:24,800 --> 00:05:26,719 Speaker 1: Download it today on iTunes.