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Plastics 101 | National Geographic
Plastics 101 | National Geographic
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(bright music)
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- [Narrator] Plastics have become
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such an entrenched part of our lives
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but what exactly is plastic and how was it made?
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Before plastic became so ubiquitous, it underwent
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a transformation from being a strictly natural product
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to being synthetically and widely produced.
0:29
Some of the earliest uses of plastic
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date as far back as 3,500 years ago
0:35
when the Olmecs of Mexico used naturally occurring plastics,
0:39
sap from gum trees, to create rubber balls.
0:43
During the mid-19th and 20th centuries,
0:45
synthetic plastics like celluloid and Bakelite,
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made their debut and were used for decades.
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On the molecular level, plastics are made of polymers
0:57
which are long flexible chains of chemical compounds.
1:01
This structure allows plastics to be easily molded
1:04
and shaped, especially, under heat and pressure.
1:08
Unlike the rubber used by the Olmecs,
1:10
most of today's plastics are manmade
1:13
and derived from fossil fuels.
1:15
Crude oil and natural gas are primary sources
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as they provide a cheap alternative
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to plastic made from plants.
1:25
The first step in the production of plastic
1:28
is the extraction of crude oil and natural gas
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from the ground.
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From there, the fossil fuels are sent to refineries
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where they are converted into several products
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including the building blocks of plastic,
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ethane from crude oil and propane from natural gas.
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Ethane and propane are then sent to a cracker plant
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to be cracked or broken down into smaller molecules.
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Ethane produces ethylene and propane becomes propylene.
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Next, a catalyst is mixed in which links
2:01
the molecules together and forms polymers called resins.
2:05
This structure allows plastics to be easily molded
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and shaped, especially, under heat and pressure.
2:11
Polymerization converts ethylene
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into the resin, polyethylene,
2:15
and propylene into polypropylene.
2:20
These resins are then melted, cooled down and chopped up
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into preproduction plastic pellets known as nurdles.
2:28
Nurdles are later transported to manufacturers
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who use heat to mold the nurdles into different types
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of plastic products.
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Many of those products actually feature information
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about their manufacturing process.
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Numbers called resin identification codes are often featured
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indicating which chemicals were used to make the plastic.
2:52
Because of plastics utility, it's global production
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has doubled about every decade.
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The amount of plastics produced since 1950
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has measured at about 9.2 billion tons,
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the weight of nearly 1,600 Great Pyramids of Giza.
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Much of this plastic ends up as trash.
3:15
Single-use plastic such as straws, grocery bags
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and packaging products are, particularly, detrimental.
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They often aren't recycled and constitute about 40%
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of all plastic waste.
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They end up damaging natural habitats, endangering wildlife
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and polluting communities around the world.
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Moving forward, a great way we can counter
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this plastic pollution is to reduce the amount
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of single-use plastics we use.
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By opting, instead, for reusable alternatives
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in our day-to-day lives, each person can make a huge impact
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in helping decrease plastic waste.
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For plastics that are already produced,
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other solutions are being explored.
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Scientists have discovered that a few organisms
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are capable of breaking down plastic material.
4:10
Wax worms and mealworms, for example, can devour plastics
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and turn them into compost.
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Another plastic-consuming organism is a microbe
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which shrinks the time plastic takes to degrade
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from hundreds of years to only a few days.
4:27
Change is happening in the production of plastics as well
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with some manufacturers turning back
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to plants for ingredients.
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Called biodegradable bioplastics,
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these materials are as durable as synthetic plastics,
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come from renewable resources
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and can, therefore, biodegrade.
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Even the rubber tree, the same plant used by the Olmecs,
4:51
is, once again, being sourced for plastic.
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Today, the tree's latex is used to create
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a range of products such as all natural latex rubber gloves,
5:01
tires and mattresses.
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The rubber tree itself is now part of a global initiative
5:09
for the natural and sustainable sourcing of plastic.
5:18
Plastics can be found almost anywhere
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but by understanding its chemical makeup
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and our uses for it, we can benefit from its versatility
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while also being mindful of its impact on our planet.
5:34
Take your pledge today to reduce single-use plastics.
