1 00:00:02,040 --> 00:00:07,120 Speaker 1: Welcome to brain Stuff from How Stuff Works, Hey, brain Stuff, 2 00:00:07,160 --> 00:00:10,240 Speaker 1: Lauren Voge obamb here. A few years ago, engineer Toby 3 00:00:10,280 --> 00:00:13,000 Speaker 1: McCartney was working in southern India with a charity that 4 00:00:13,039 --> 00:00:16,919 Speaker 1: aided pickers who worked at landfill sites harvesting reusable items 5 00:00:16,920 --> 00:00:20,600 Speaker 1: and selling them. McCartney discovered that the plastic waste they 6 00:00:20,600 --> 00:00:23,439 Speaker 1: retrieved was being put into potholes and roads, dused with 7 00:00:23,440 --> 00:00:26,480 Speaker 1: gasoline and set a fire. When the plastic melted into 8 00:00:26,480 --> 00:00:29,840 Speaker 1: the holes and then hardened, it filled them. When McCartney 9 00:00:29,840 --> 00:00:32,040 Speaker 1: returned to Scotland, he told two of his friends about 10 00:00:32,080 --> 00:00:34,879 Speaker 1: what he had seen. As one of them, Gordon Reid, recalls, 11 00:00:35,120 --> 00:00:37,440 Speaker 1: they decided that it would work better to use plastic 12 00:00:37,479 --> 00:00:40,640 Speaker 1: waste to create a new type of materials specifically designed 13 00:00:40,640 --> 00:00:43,440 Speaker 1: for use in roads. After a year of research, they 14 00:00:43,440 --> 00:00:46,280 Speaker 1: developed a method for transforming a mix of industrial and 15 00:00:46,320 --> 00:00:49,280 Speaker 1: consumer plastic waste into pellets of a new material that 16 00:00:49,280 --> 00:00:52,760 Speaker 1: could replace bitumen, the oil based ceiling material that holds 17 00:00:52,800 --> 00:00:57,760 Speaker 1: asphalt together in roads. Since Reid's company Mcgreeber started operations 18 00:00:57,760 --> 00:01:01,560 Speaker 1: in April of sixteen, the companies recycled plastic road building 19 00:01:01,600 --> 00:01:04,479 Speaker 1: material has been used to build roadways in places ranging 20 00:01:04,480 --> 00:01:08,319 Speaker 1: from Australia to Dubai. Read says we've got roads on 21 00:01:08,360 --> 00:01:11,360 Speaker 1: every continent, and we've had interest from round about fifty 22 00:01:11,400 --> 00:01:14,560 Speaker 1: countries in the world. The company currently is having discussions 23 00:01:14,560 --> 00:01:17,280 Speaker 1: with the University in California about building a test road 24 00:01:17,440 --> 00:01:20,319 Speaker 1: to demonstrate that its plastics are compatible with standards in 25 00:01:20,319 --> 00:01:24,280 Speaker 1: the United States. According to Read, using recycled plastic for 26 00:01:24,360 --> 00:01:27,560 Speaker 1: road buildings sounds simple, but it actually requires a complex 27 00:01:27,600 --> 00:01:31,440 Speaker 1: process to create the right material. He explained, different plastics 28 00:01:31,440 --> 00:01:34,240 Speaker 1: do different things to bitterman. If you use the wrong mix, 29 00:01:34,360 --> 00:01:38,319 Speaker 1: it can actually make the bitterman more brittle. Mcgreeper avoids 30 00:01:38,400 --> 00:01:41,040 Speaker 1: using pet bottles and other types of plastic that are 31 00:01:41,040 --> 00:01:44,800 Speaker 1: easily recycled, and instead concentrates on types of waste plastic 32 00:01:44,880 --> 00:01:47,880 Speaker 1: that might otherwise end up buried in the ground. Read 33 00:01:47,920 --> 00:01:49,920 Speaker 1: declined to go into too much detail as so not 34 00:01:50,000 --> 00:01:53,880 Speaker 1: to reveal too much about mcgreeber's proprietary process. In addition 35 00:01:53,920 --> 00:01:56,680 Speaker 1: to keeping plastic out of landfills, the company says it's 36 00:01:56,720 --> 00:01:59,520 Speaker 1: plastic road materials can save about a ton in carbon 37 00:01:59,560 --> 00:02:03,080 Speaker 1: dioxide output for each town of Benemen that the plastic replaces. 38 00:02:03,680 --> 00:02:06,400 Speaker 1: The company has developed different types of road building plastic 39 00:02:06,440 --> 00:02:09,800 Speaker 1: four different environments. One variety is designed for roads in 40 00:02:09,840 --> 00:02:12,799 Speaker 1: such places as the Middle East, where more tensile strength 41 00:02:12,840 --> 00:02:15,960 Speaker 1: is needed to resist asphalts tendency to deform from heat. 42 00:02:16,480 --> 00:02:19,040 Speaker 1: Another is designed to be more flexible and resist the 43 00:02:19,200 --> 00:02:22,600 Speaker 1: freeze thaw cycle in colder places such as Canada or Scotland. 44 00:02:22,639 --> 00:02:27,080 Speaker 1: Read says mcgreeber's current products are capable of replacing between 45 00:02:27,120 --> 00:02:30,120 Speaker 1: six and twenty of the bitumen in roads, but Read 46 00:02:30,200 --> 00:02:33,200 Speaker 1: is hopeful that within two years improved versions will replace 47 00:02:33,200 --> 00:02:37,480 Speaker 1: as much as Read says that mcgreeber's plastic road materials 48 00:02:37,480 --> 00:02:40,800 Speaker 1: physically bind with betterman which prevents it from breaking loose 49 00:02:40,840 --> 00:02:44,239 Speaker 1: and getting into the environment. In the US, plastic is 50 00:02:44,280 --> 00:02:47,480 Speaker 1: already being used in road maintenance. University of Texas at 51 00:02:47,560 --> 00:02:51,480 Speaker 1: Arlington civil engineer Professor Sahodat Hussein, director of the School 52 00:02:51,520 --> 00:02:55,400 Speaker 1: Solid Waste Institute for Sustainability, has turned to recycled plastic 53 00:02:55,480 --> 00:02:58,000 Speaker 1: as a way to solve the problem of unstable soil 54 00:02:58,240 --> 00:03:01,760 Speaker 1: on highway slopes, which unually can cause the road surface 55 00:03:01,760 --> 00:03:05,040 Speaker 1: to fail. As well. He's developed a technology for taking 56 00:03:05,040 --> 00:03:08,760 Speaker 1: plastic from landfills and then recycling it to manufactured giant 57 00:03:08,880 --> 00:03:12,440 Speaker 1: pins that are inserted into the falling soil to stabilize it. 58 00:03:13,080 --> 00:03:16,760 Speaker 1: Causean explained via email that the recycled plastic pin quote 59 00:03:16,880 --> 00:03:20,280 Speaker 1: has been successfully tested as a laterally loaded pile in 60 00:03:20,320 --> 00:03:24,360 Speaker 1: different highway slope stabilization projects in the state of Texas, Iowa, 61 00:03:24,440 --> 00:03:27,799 Speaker 1: and Missouri. The Texas Department of Transportation has adopted the 62 00:03:27,840 --> 00:03:31,760 Speaker 1: recycled plastic pin as one of their approved slope stabilization methods. 63 00:03:32,800 --> 00:03:35,160 Speaker 1: It takes just three to four minutes to install each 64 00:03:35,200 --> 00:03:37,680 Speaker 1: of the pins in the ground, so an entire unstable 65 00:03:37,760 --> 00:03:40,560 Speaker 1: area can be shored up in a few days. He said. 66 00:03:40,960 --> 00:03:43,120 Speaker 1: Once the pin is installed into the ground, it is 67 00:03:43,200 --> 00:03:46,440 Speaker 1: less susceptible to degradation, which makes it a long lasting 68 00:03:46,480 --> 00:03:50,880 Speaker 1: solution for slope repair. Each recycled pin utilizes about five 69 00:03:50,960 --> 00:03:54,000 Speaker 1: hundred plastic soda bottles. At one of the demonstration sites, 70 00:03:54,080 --> 00:03:57,320 Speaker 1: Hussein's research group puts six hundred plastic pins into the ground, 71 00:03:57,720 --> 00:04:00,400 Speaker 1: making use of some three hundred thousand plastic models that 72 00:04:00,440 --> 00:04:03,800 Speaker 1: otherwise would have ended up in landfills. Coussine thinks that 73 00:04:03,800 --> 00:04:07,080 Speaker 1: the Chinese government's recent decision to ban imports of plastic 74 00:04:07,080 --> 00:04:10,680 Speaker 1: waste for recycling could create an opportunity for US entrepreneurs 75 00:04:10,720 --> 00:04:14,320 Speaker 1: to make road materials. China imported seven hundred and seventy 76 00:04:14,400 --> 00:04:17,080 Speaker 1: six thousand metric tons of plastic waste from the United 77 00:04:17,120 --> 00:04:21,240 Speaker 1: States in two six. Hussein said, I am positive more 78 00:04:21,240 --> 00:04:25,080 Speaker 1: and more roads will be constructed using recycled plastics, but 79 00:04:25,160 --> 00:04:27,120 Speaker 1: he does note that more work needs to be done 80 00:04:27,160 --> 00:04:30,520 Speaker 1: to develop new methods, including full scale testing and life 81 00:04:30,520 --> 00:04:39,400 Speaker 1: cycle analysis of roads containing plastic materials. Today's episode was 82 00:04:39,400 --> 00:04:42,040 Speaker 1: written by Patrick J. Kaiger and produced by Tyler Clang. 83 00:04:42,400 --> 00:04:44,760 Speaker 1: Brain Stuff has merch now you can get phone cases, 84 00:04:44,800 --> 00:04:47,960 Speaker 1: tote bags, and of course T shirts. Every purchase helps 85 00:04:48,040 --> 00:04:50,320 Speaker 1: keep the show going and supports us directly. You can 86 00:04:50,360 --> 00:04:53,360 Speaker 1: find all that stuff at t public dot com slash 87 00:04:53,480 --> 00:04:55,640 Speaker 1: brain Stuff. For more on this and lots of other 88 00:04:55,680 --> 00:04:58,800 Speaker 1: forward thinking topics, visit our home planet, how Stuff Works 89 00:04:58,839 --> 00:05:10,599 Speaker 1: dot com.