0:00:06 > 0:00:11This is the vibrant heart of a 21st century city.
0:00:11 > 0:00:15There's something strange but wonderful about Piccadilly Circus.
0:00:15 > 0:00:18Strange because, as far as the eye can see,
0:00:18 > 0:00:19there's nothing natural.
0:00:19 > 0:00:23There's not a tree, not a flower, not a blade of grass.
0:00:23 > 0:00:25But wonderful because we made it.
0:00:27 > 0:00:31We've transformed matter to create the world that we live in.
0:00:38 > 0:00:43My name is Mark Miodownik, and as a materials scientist
0:00:43 > 0:00:45I've spent my life trying to understand
0:00:45 > 0:00:47what's hidden deep beneath the surface
0:00:47 > 0:00:50of everything that makes up our modern world.
0:00:57 > 0:01:01For me, the story of how materials have driven human civilisation
0:01:01 > 0:01:04from the Stone Age to the Silicon Age
0:01:04 > 0:01:06is the most exciting story in science.
0:01:08 > 0:01:12Without our mastery of the stuff that we found around us,
0:01:12 > 0:01:15we would have no buildings, no cars,
0:01:15 > 0:01:18no roads, no art.
0:01:18 > 0:01:20Nothing.
0:01:20 > 0:01:25This is the story of how we created our 21st century world,
0:01:25 > 0:01:28how we unlocked the secrets of the raw materials of our planet
0:01:28 > 0:01:29and created our future.
0:01:31 > 0:01:34First, metals.
0:01:34 > 0:01:36From copper and bronze to modern super alloys,
0:01:36 > 0:01:39we'll reveal how the atomic structure of metals
0:01:39 > 0:01:42gives them their strength.
0:01:44 > 0:01:47Next, ceramics. We'll discover the intriguing properties
0:01:47 > 0:01:51that have allowed them to shape the modern world.
0:01:51 > 0:01:53'From concrete...
0:01:55 > 0:01:58'..to fibre optics...' It bends.
0:01:58 > 0:01:59'and superconductors.'
0:01:59 > 0:02:01The magnet floats on air.
0:02:01 > 0:02:03'Finally, plastics.
0:02:03 > 0:02:08'We'll explore how scientists trying to improve natural substances,
0:02:08 > 0:02:14'like rubber, created a whole new world of modern synthetic materials,
0:02:14 > 0:02:18'from Bakelite to graphene.'
0:02:25 > 0:02:28This is where our ancestors first settled.
0:02:28 > 0:02:32It's where East meets West, where Africa meets Asia.
0:02:34 > 0:02:37Underneath my feet, the Earth's crust is shifting.
0:02:39 > 0:02:41And the geology here gave our ancestors
0:02:41 > 0:02:46access to something that would change their world.
0:02:48 > 0:02:51This is one of the first places on Earth
0:02:51 > 0:02:53that man stepped out of the Stone Age
0:02:53 > 0:02:56and transformed rock into metal.
0:02:56 > 0:02:59And it all started with copper.
0:03:01 > 0:03:04It's these green streaks that may have been the first clue
0:03:04 > 0:03:07there was something a bit special about this rock.
0:03:07 > 0:03:11Somehow, we worked out that when you've got this type of rock,
0:03:11 > 0:03:14you can do something amazing with it.
0:03:18 > 0:03:22We don't really know when our ancestors first discovered
0:03:22 > 0:03:24what this marvellous green rock can do.
0:03:24 > 0:03:26They might have just ground it up
0:03:26 > 0:03:29to use it as a powder to decorate their pottery,
0:03:29 > 0:03:33or maybe it happened to be just lying by the fire.
0:03:33 > 0:03:37But either way, they discovered something really rather marvellous
0:03:37 > 0:03:40about what this stuff can do if you add it to a fire.
0:03:40 > 0:03:44Now, the thing about the fire is, you need it to be very, very hot
0:03:44 > 0:03:47and for that you need a lot of air,
0:03:47 > 0:03:50and that's why they built their fires on hillsides.
0:03:50 > 0:03:52These hillsides are extremely windy,
0:03:52 > 0:03:55so the air is being funnelled into the fire.
0:03:55 > 0:03:57It's actually a genius idea.
0:03:57 > 0:04:00And then, when they'd got a very hot fire,
0:04:00 > 0:04:03they added the green rock.
0:04:03 > 0:04:07And then they kept the temperature high for hours, and they waited.
0:04:14 > 0:04:16So when the fire died down,
0:04:16 > 0:04:21they would have found bits of a hard stone, black stone,
0:04:21 > 0:04:23but amongst that black stone,
0:04:23 > 0:04:28look, there's tiny little shiny bits of metal.
0:04:28 > 0:04:32They'd transformed rock into metal, it's absolutely extraordinary!
0:04:32 > 0:04:35Here we have rock... I mean, there's rock everywhere,
0:04:35 > 0:04:38but they'd found the power of transformation.
0:04:40 > 0:04:44Look! Look how bright that is! A bright piece of copper.
0:04:44 > 0:04:48We know they did it on this hillside because we've found the remnants
0:04:48 > 0:04:51from early smelting of our ancestors.
0:04:51 > 0:04:53So they did that here,
0:04:53 > 0:04:57and this was the beginning of human civilisation,
0:04:57 > 0:05:00the age of metals.
0:05:13 > 0:05:15Our ancestors realised that with copper,
0:05:15 > 0:05:18they could make strong tools,
0:05:18 > 0:05:21better than anything they'd had before.
0:05:21 > 0:05:25This copper chisel represents the leap out of the Stone Age.
0:05:25 > 0:05:27Everything we have in our civilisation today
0:05:27 > 0:05:29is due to metal tools like this.
0:05:29 > 0:05:31If they get blunt, we can sharpen them.
0:05:31 > 0:05:34If they get bent, we can re-straighten them.
0:05:34 > 0:05:36If they get damaged, we can repair them.
0:05:36 > 0:05:39It's simply the perfect material for tools.
0:05:41 > 0:05:43Nothing else our ancestors had in their world
0:05:43 > 0:05:48could have done this - not stone, not bone, not wood.
0:05:51 > 0:05:54So what's so special about metal?
0:05:54 > 0:05:57It's all down to its inner structure.
0:05:59 > 0:06:03Metals are made of crystals, and that's a very surprising fact,
0:06:03 > 0:06:05because they don't seem to behave
0:06:05 > 0:06:08anything like the crystals we are more familiar with.
0:06:08 > 0:06:11I'll show you what I mean. I've got a quartz crystal here.
0:06:11 > 0:06:13That's what you mean when you say "crystal".
0:06:13 > 0:06:17And this is what a quartz crystal says when you hit it with a hammer.
0:06:20 > 0:06:22You see? That's what we think of
0:06:22 > 0:06:25when we think of crystals being hit with a hammer.
0:06:25 > 0:06:30But if I say to you that this piece of metal is made of crystals,
0:06:30 > 0:06:32you know already that it's not going to do that.
0:06:32 > 0:06:35It's going to be quite malleable, I can do this.
0:06:35 > 0:06:39In fact, that's how you work metal, you change its shape.
0:06:39 > 0:06:43And that's...that's really strange, because that means
0:06:43 > 0:06:48that the crystals in this metal are changing shape instead of exploding.
0:06:49 > 0:06:50Inside the metal crystal,
0:06:50 > 0:06:54the basic building blocks of everything in the universe, atoms,
0:06:54 > 0:06:58are arranged in a regular lattice structure.
0:06:58 > 0:06:59But they're not static.
0:07:02 > 0:07:06When they're hit, metals can shuffle atoms from one side to the other,
0:07:06 > 0:07:08like a Mexican wave.
0:07:10 > 0:07:12They can move, rearrange themselves,
0:07:12 > 0:07:15and this is why the crystal can change shape.
0:07:18 > 0:07:20Metals alone behave like this.
0:07:20 > 0:07:23As well as not shattering when you hit them,
0:07:23 > 0:07:25they actually get stronger.
0:07:29 > 0:07:32The impact creates waves of shuffling atoms
0:07:32 > 0:07:35which collide with each other and create blockages.
0:07:35 > 0:07:38These make it harder for the atoms to shuffle around,
0:07:38 > 0:07:40making the metal stronger.
0:07:43 > 0:07:45So the more hammering you do,
0:07:45 > 0:07:47the more blockages you form in the crystal,
0:07:47 > 0:07:49and so the stronger the metal gets.
0:07:51 > 0:07:55It was the strength of metal over stone and wood
0:07:55 > 0:07:57that became its main attraction.
0:08:01 > 0:08:02With metal tools,
0:08:02 > 0:08:07our ancestors could dream up projects on a massive scale.
0:08:09 > 0:08:13It's believed the limestone blocks that built the pyramids of Egypt
0:08:13 > 0:08:15were carved using copper chisels.
0:08:19 > 0:08:21But soon copper wasn't enough.
0:08:21 > 0:08:26Our love affair with metals consumed us.
0:08:26 > 0:08:29Here on the shores of what's now Israel,
0:08:29 > 0:08:32metals from distant lands were traded.
0:08:32 > 0:08:35And it was one of these, tin, that moved on the story of metals,
0:08:35 > 0:08:40as our ancestors began to mix metals together.
0:08:40 > 0:08:44So they took some copper...some tin,
0:08:44 > 0:08:47and they melted them together to make a mixture,
0:08:47 > 0:08:49which we call an alloy.
0:08:49 > 0:08:52And they created a new metal, bronze.
0:08:55 > 0:08:57Bronze was the creation of Man the metal-smith,
0:08:57 > 0:08:59rather than a gift of nature,
0:08:59 > 0:09:04and it gave its name to a new era, the Bronze Age.
0:09:05 > 0:09:08Now, this is a nail made out of pure copper,
0:09:08 > 0:09:12and as metals go, copper's pretty weak.
0:09:12 > 0:09:14Have a look at this.
0:09:18 > 0:09:21After a while, it just can't get any further,
0:09:21 > 0:09:24and so the metal itself buckles.
0:09:24 > 0:09:28If I do the same with a tin nail... let's see what happens.
0:09:28 > 0:09:31Tin is actually softer than copper, even.
0:09:32 > 0:09:35That's a real joke for a nail, isn't it?
0:09:35 > 0:09:37But here's the odd thing.
0:09:37 > 0:09:41The mixture, a bronze nail...
0:09:41 > 0:09:43well, this is much stronger.
0:09:44 > 0:09:45Ha-ha-ha-ha!
0:09:47 > 0:09:50So that's odd, isn't it? You add two soft metals together,
0:09:50 > 0:09:54and you get something much harder and much stronger.
0:09:54 > 0:09:55How do you explain that?
0:09:57 > 0:10:00In bronze, the tin atoms replace some of the copper atoms,
0:10:00 > 0:10:03which are smaller.
0:10:03 > 0:10:06This interferes with the lattice structure,
0:10:06 > 0:10:11making it more difficult for the atoms to shuffle across the crystal.
0:10:11 > 0:10:13This makes the new alloy much stronger.
0:10:18 > 0:10:20The strength of bronze
0:10:20 > 0:10:23gave us the means not only to build, but to destroy.
0:10:24 > 0:10:26As well as tools,
0:10:26 > 0:10:29we made the swords and shields of conquest and dominion.
0:10:31 > 0:10:33Bronze propelled the evolution
0:10:33 > 0:10:36of a new, complex, more technological society.
0:10:36 > 0:10:39It also created new occupations,
0:10:39 > 0:10:42such as mining, manufacturing and trading metals.
0:10:44 > 0:10:47Since then, we've continued to combine metals,
0:10:47 > 0:10:51making new and stronger alloys.
0:10:51 > 0:10:55And the most successful combination in history is steel,
0:10:55 > 0:10:57an alloy of iron and carbon.
0:10:59 > 0:11:0490% of the metal we make today is steel.
0:11:05 > 0:11:09It allowed as to travel across the globe by rail...
0:11:11 > 0:11:12..by road...
0:11:12 > 0:11:14..and by sea.
0:11:14 > 0:11:20Strong, reliable steel enabled us to build great cities.
0:11:20 > 0:11:23The construction industry would be nowhere without steel.
0:11:23 > 0:11:26The buildings around me wouldn't be standing
0:11:26 > 0:11:28without steel at their heart.
0:11:28 > 0:11:33And we've continued our quest to create better, stronger alloys.
0:11:33 > 0:11:36There's been a huge flowering of metallurgy
0:11:36 > 0:11:38in the last 60 years.
0:11:38 > 0:11:42And there seemed to be no problem we couldn't solve.
0:11:43 > 0:11:46'And we were facing another.
0:11:46 > 0:11:50'How to get a metal to work in the most extreme environment on Earth.
0:11:50 > 0:11:52'A jet engine.'
0:11:52 > 0:11:55Let me show you what I mean.
0:11:55 > 0:11:56Inside jet engines,
0:11:56 > 0:11:59is an incredibly difficult place for metals to be.
0:11:59 > 0:12:01Extremely hot temperatures.
0:12:01 > 0:12:04Extremely high stress they had to put up with.
0:12:04 > 0:12:05So they had to design a new alloy
0:12:05 > 0:12:07that could cope with this environment.
0:12:07 > 0:12:09And it was called "superalloy".
0:12:09 > 0:12:12So-called because it was so super.
0:12:12 > 0:12:14Here's a bit of it here.
0:12:14 > 0:12:16I'm going to pit it against our old friend steel,
0:12:16 > 0:12:18who, of course, we know and love.
0:12:18 > 0:12:21I'm going to hang weights off these two wires.
0:12:21 > 0:12:22It's the same weight, in both cases,
0:12:22 > 0:12:26and they're the same thickness of wire.
0:12:26 > 0:12:27So, now they're under the same stress.
0:12:27 > 0:12:30Now, I'm going to make it harder for them,
0:12:30 > 0:12:34because they'll have to hold that up while under huge temperatures,
0:12:34 > 0:12:37which means me putting a blowtorch on them.
0:12:37 > 0:12:41OK, are you guys ready? Let's go.
0:12:46 > 0:12:49So, the steel wire succumbed within a few seconds.
0:12:49 > 0:12:53And that's only a fraction of the heat inside a jet engine.
0:12:56 > 0:12:59I could be here all day with the superalloy.
0:12:59 > 0:13:01This superalloy can take this.
0:13:03 > 0:13:06I know these metals all look the same, but inside this superalloy
0:13:06 > 0:13:08is the most exquisite microstructure,
0:13:08 > 0:13:12that was designed for this purpose.
0:13:12 > 0:13:14To control the movement inside the metal,
0:13:14 > 0:13:17and make it unbelievably strong at high temperatures.
0:13:20 > 0:13:23'The cubes of material within the superalloy
0:13:23 > 0:13:25'are called "gamma prime crystals".
0:13:25 > 0:13:26'They sit within the alloy,
0:13:26 > 0:13:28'affecting its ability to change shape.
0:13:30 > 0:13:32'Which makes it incredibly strong,
0:13:32 > 0:13:35'even at temperatures close to its melting point.'
0:13:38 > 0:13:39That's pretty impressive,
0:13:39 > 0:13:41and, as the jet age progressed,
0:13:41 > 0:13:44scientists and engineers pushed the technology,
0:13:44 > 0:13:47to create more and more powerful engines.
0:13:53 > 0:13:56'Superalloys were the strongest metals
0:13:56 > 0:13:57'we had ever created.
0:13:57 > 0:14:01But metals alone haven't shaped our modern world.
0:14:13 > 0:14:15I'm standing on top of the modern world,
0:14:15 > 0:14:20on a structure built from some of the most extraordinary materials that humans have invented.
0:14:20 > 0:14:23Everything around me is man-made.
0:14:23 > 0:14:27And it's built of this -
0:14:27 > 0:14:29sand and clay.
0:14:30 > 0:14:33We've transformed sand into transparent glass.
0:14:33 > 0:14:37Malleable clay has metamorphosised into hard earthenware
0:14:37 > 0:14:41and brittle porcelain.
0:14:41 > 0:14:45These miracle materials are ceramics.
0:14:45 > 0:14:49All forged from the stuff of the Earth.
0:14:50 > 0:14:52And the one I think has had the greatest impact
0:14:52 > 0:14:55on the ancient and modern worlds
0:14:55 > 0:14:57was invented by the Romans.
0:15:01 > 0:15:06Their inspiration may have come from volcanoes,
0:15:06 > 0:15:09like Mount Vesuvius and Etna.
0:15:09 > 0:15:14When they erupt, they spew out ash and the Romans noticed that,
0:15:14 > 0:15:18when the ash got wet, it hardened and became almost as hard as stone.
0:15:18 > 0:15:23The Romans saw the potential to make a powerful new material -
0:15:23 > 0:15:25concrete.
0:15:33 > 0:15:39'Chris Brandon has studied Roman concrete for over 20 years.
0:15:39 > 0:15:41'And he's going to help me make some.
0:15:44 > 0:15:48'We're using volcanic ash called pozzolana ash
0:15:48 > 0:15:52'and adding burnt limestone made into a putty.
0:15:52 > 0:15:55'The same ingredients the Romans would have used.'
0:15:56 > 0:15:59How do we know that Romans made concrete this way?
0:15:59 > 0:16:02Is it written down somewhere, a recipe?
0:16:02 > 0:16:07Yes, there is a recipe in Vitruvius, Pliny also wrote about it.
0:16:10 > 0:16:15'We're not heating our mixture, but heat is still fundamental'.
0:16:16 > 0:16:21The pozzolana ash was formed as minerals reacted
0:16:21 > 0:16:23in the extreme heat of a volcano.
0:16:24 > 0:16:27And the Romans heated limestone themselves.
0:16:29 > 0:16:32As the heat drove off carbon dioxide,
0:16:32 > 0:16:36it turns limestone into the very reactive burnt limestone -
0:16:36 > 0:16:38quicklime.
0:16:41 > 0:16:44'We're adding water right now to make the cement paste.
0:16:44 > 0:16:47'That's the key ingredient of concrete.'
0:16:47 > 0:16:50We must make sure it is a stiff mix.
0:16:51 > 0:16:53You can see this is a paste now,
0:16:53 > 0:16:56something I can mould and shape into whatever I want.
0:16:58 > 0:17:02The water kicks off a complex set of chemical reactions.
0:17:05 > 0:17:07New compounds are formed.
0:17:07 > 0:17:12Some are gels which harden into these fibre-like fibrils,
0:17:12 > 0:17:16which can be seen magnified many thousand times.
0:17:18 > 0:17:22The fibrils grow into a hard, interlocking mesh
0:17:22 > 0:17:26that is the basis of concrete's strength.
0:17:26 > 0:17:30It's a reaction that can keep going for years,
0:17:30 > 0:17:33and the concrete goes on getting harder and harder.
0:17:39 > 0:17:43It was concrete that gave the Romans their great structures.
0:17:44 > 0:17:49Their amphitheatres, stadiums and the Dome of the Pantheon.
0:17:50 > 0:17:53Built almost 2,000 years ago,
0:17:53 > 0:17:58spanning a distance of more than 40 metres, the Pantheon still
0:17:58 > 0:18:02has the largest unreinforced concrete dome in the world.
0:18:07 > 0:18:10But the Romans weren't the only ones to recognise
0:18:10 > 0:18:13the huge potential of concrete.
0:18:13 > 0:18:15TRAIN WHISTLE BLOWS
0:18:15 > 0:18:19Victorians too used it to create magnificent feats of engineering.
0:18:19 > 0:18:24But they also realised that it had one fatal flaw.
0:18:25 > 0:18:30Dr Phil Purnell has been studying concrete for over 15 years.
0:18:30 > 0:18:33Well, today, Mark,
0:18:33 > 0:18:35we're going to get you to walk a concrete plank to give us
0:18:35 > 0:18:38some indication of how concrete could let us down if not careful.
0:18:38 > 0:18:42- Wow, it really is a concrete plank. - It certainly is, yes.
0:18:42 > 0:18:45- We're going to get you to walk across it.- OK.
0:18:45 > 0:18:47So if you would like to sort of get onto that there.
0:18:47 > 0:18:49I'm slightly nervous about this, because I can't
0:18:49 > 0:18:53imagine that there is a good reason for me walking a plank.
0:18:53 > 0:18:55As you gently inch your weight across the plank,
0:18:55 > 0:18:58you're making it bend, you're bending the concrete.
0:18:58 > 0:19:01And when you bend something, the top of that goes into crushing,
0:19:01 > 0:19:04it's being crushed, it goes into compression.
0:19:04 > 0:19:09The bottom of it is pulled apart and goes into what we call tension.
0:19:09 > 0:19:13'As the plank curves a tiny bit under my weight,
0:19:13 > 0:19:17'the top surface becomes concave and is squashed,
0:19:17 > 0:19:19'while the bottom is stretched.'
0:19:21 > 0:19:23Of course, as I get closer to the middle,
0:19:23 > 0:19:25I'm making the plank work much harder.
0:19:25 > 0:19:27When you're in the middle, you have
0:19:27 > 0:19:30a maximum crushing on the top and a maximum pulling underneath.
0:19:30 > 0:19:32- Concrete is very, very good... - CRASH!
0:19:32 > 0:19:35..but as you can see, very, very poor in tension.
0:19:35 > 0:19:39- So what we've demonstrated... - That's exactly what you don't want a building to do!- Exactly.
0:19:39 > 0:19:42- You really don't want that to happen.- OK, wow.
0:19:42 > 0:19:45This is actually a thick piece of concrete, I'm really surprised.
0:19:45 > 0:19:49That's as thick as your concrete floors at home or an office block.
0:19:49 > 0:19:51- That's a genuine thickness of concrete.- Wow.
0:19:53 > 0:19:58'The reason concrete can snap like this is down to its inner structure.'
0:20:01 > 0:20:06Concrete isn't entirely solid. It's riddled with tiny holes.
0:20:07 > 0:20:10When it's compressed, the holes close up
0:20:10 > 0:20:12and the concrete stays strong.
0:20:14 > 0:20:17But when it's under tension, the holes open up.
0:20:17 > 0:20:21Stress will concentrate at the edges of the holes.
0:20:21 > 0:20:24Here, cracks can start...
0:20:26 > 0:20:30..and the stress can be powerful enough to split the concrete.
0:20:32 > 0:20:37As the cracks grow, they join up with other cracks
0:20:37 > 0:20:40and can rip the concrete apart.
0:20:45 > 0:20:49So, to build bigger, we would need to find a way
0:20:49 > 0:20:54of working around concrete's one great weakness.
0:20:56 > 0:21:00So, what is this trick? What's the answer to making concrete stronger,
0:21:00 > 0:21:03resisting these bending forces?
0:21:03 > 0:21:07Well, back in the 1850s, there was a plasterer from Newcastle,
0:21:07 > 0:21:11called Mr Wilkinson, and he was making concrete floor slabs.
0:21:11 > 0:21:14And what he noticed is that these slabs have a tendency
0:21:14 > 0:21:17to crack in between the joists.
0:21:17 > 0:21:20Just like my unfortunate experience with the plank.
0:21:20 > 0:21:23Exactly like your unfortunate experience with the plank, yes.
0:21:23 > 0:21:26So Wilkinson noticed where the cracks were appearing
0:21:26 > 0:21:30in his concrete floor slabs and he had an idea, and a very bright idea.
0:21:30 > 0:21:33And he took some barrel hoops,
0:21:33 > 0:21:37took some of the flat hoops that go around and hold a barrel together,
0:21:37 > 0:21:40and he placed them in the concrete where he noticed the cracks
0:21:40 > 0:21:44were appearing, where he knew we had to resist these pulling forces.
0:21:44 > 0:21:49- So he invented reinforced concrete? - He did. Back in 1853. Yes.
0:21:49 > 0:21:53- What a dude.- Absolutely! He laid the foundations for modern urban life.
0:21:53 > 0:21:58Without reinforced concrete, nothing we see around us would exist.
0:22:00 > 0:22:03Reinforced concrete might seem simple,
0:22:03 > 0:22:06but it works because steel is the perfect partner for concrete.
0:22:07 > 0:22:10They both share a surprising quality.
0:22:11 > 0:22:17They expand and contract at the same rate when they get hot or cold.
0:22:17 > 0:22:22And unlike concrete, steel is strong when it's under tension.
0:22:22 > 0:22:26It bends without breaking, like concrete does.
0:22:33 > 0:22:35As we learned more about materials,
0:22:35 > 0:22:41we found it easier to find clever ways to fix problems.
0:22:41 > 0:22:47For instance, we didn't try to stop concrete cracking completely,
0:22:47 > 0:22:49just to control it.
0:22:49 > 0:22:53So, to test this beam, we're pushing down on it repeatedly
0:22:53 > 0:22:57with a force of about 2.5 tonnes, so we are putting it under the sort
0:22:57 > 0:23:00of loads that we might expect, for example, a rail or road bridge
0:23:00 > 0:23:03to be put under when large vehicles go over the top of it.
0:23:03 > 0:23:06I can see it's bending. It's bending quite a lot.
0:23:06 > 0:23:07It's bending quite a lot, yes.
0:23:07 > 0:23:09I hate to tell you this, but it's cracking.
0:23:09 > 0:23:11It's cracking quite considerably.
0:23:11 > 0:23:14But look at the difference compared to our plank in the other room.
0:23:14 > 0:23:17Here, our cracks are only travelling a certain way up,
0:23:17 > 0:23:21because what is happening is, the steel is holding the beam together,
0:23:21 > 0:23:24the steel is holding that crack together.
0:23:24 > 0:23:27If I just traced this crack out, to highlight it a bit more clearly.
0:23:27 > 0:23:31We can see the crack is travelling up from the bottom of the beam.
0:23:31 > 0:23:34But it stops roughly halfway up the beam,
0:23:34 > 0:23:38so I will just raw a dotted line there to show where it stopped.
0:23:38 > 0:23:40And everything above that dotted line is
0:23:40 > 0:23:44going into the crushing force, into compression.
0:23:44 > 0:23:48Everything below that dotted line is being pulled, going into tension.
0:23:48 > 0:23:50So above the line, the concrete is doing the work.
0:23:50 > 0:23:53Below the line, the steel is doing the work.
0:23:53 > 0:23:56So we're getting the very best out of both materials.
0:23:56 > 0:24:00- So that crack is stable? Nothing to worry about?- It's perfectly stable.
0:24:00 > 0:24:03All reinforced concrete buildings are cracked to some degree,
0:24:03 > 0:24:06and the important thing, when designing reinforced concrete,
0:24:06 > 0:24:08is to make sure that you have lots and lots
0:24:08 > 0:24:12and lots of small cracks instead of one very, very big crack.
0:24:16 > 0:24:19Most people see concrete as drab, grey and ugly.
0:24:19 > 0:24:21It hasn't got many fans.
0:24:21 > 0:24:23But I think it's an extraordinary material.
0:24:23 > 0:24:26You can build man-made mountains with it.
0:24:26 > 0:24:27Buildings of any shape you want.
0:24:27 > 0:24:30Structures that will last for thousands of years.
0:24:30 > 0:24:33And that's the secret of concrete's success.
0:24:34 > 0:24:38Many of the iconic structures of our era, the Sydney Opera House,
0:24:38 > 0:24:44the Millau Viaduct, the tallest bridge in the world,
0:24:44 > 0:24:49and Dubai's Burj Khalifa, the world's tallest building,
0:24:49 > 0:24:51wouldn't exist without reinforced concrete.
0:24:54 > 0:24:58Reinforced concrete is flexible and versatile and it's freed us
0:24:58 > 0:25:01from the limitations of stone and brick.
0:25:01 > 0:25:06In the age of concrete, the only limitation is our imagination.
0:25:14 > 0:25:18Ceramics are now shaping society in ways that are more profound
0:25:18 > 0:25:19than the buildings we live in.
0:25:22 > 0:25:26We've discovered that, at the very small-scale,
0:25:26 > 0:25:28and at extreme temperatures,
0:25:28 > 0:25:32these materials behave in ways that we just hadn't imagined.
0:25:33 > 0:25:38And that's propelled us into the information age.
0:25:41 > 0:25:44'It's a story that didn't begin in a high-tech lab,
0:25:44 > 0:25:49'but in the dentist's chair.' At the beginning of the 20th century,
0:25:49 > 0:25:53inventors realised that bent quartz rods could carry light.
0:25:53 > 0:25:57And so they created the dental illuminator.
0:25:57 > 0:26:02'Then, a German medical student took the idea further.
0:26:02 > 0:26:05'He assembled lots of thin fibres into bundles
0:26:05 > 0:26:09'to see if he could transmit not just light, but an image.'
0:26:09 > 0:26:14His goal was to look at the inaccessible parts of the body during surgery.
0:26:14 > 0:26:17'And fibre-optic bundles were perfect.
0:26:17 > 0:26:20'They could follow the contours of the body,
0:26:20 > 0:26:22'because of a surprising property of glass.'
0:26:23 > 0:26:28Glass of the everyday scale is brittle and stiff,
0:26:28 > 0:26:32but at the microscale, it behaves totally differently.
0:26:32 > 0:26:34It bends.
0:26:36 > 0:26:39You can only see this amazing elastic property of glass
0:26:39 > 0:26:42in something as thin as an optical fibre,
0:26:42 > 0:26:44the diameter of a human hair.
0:26:48 > 0:26:51Atoms in glass are connected by bonds,
0:26:51 > 0:26:54which behave a little like stiff springs.
0:26:55 > 0:26:57This means glass can bend a tiny bit.
0:27:00 > 0:27:05The finer the glass thread, the less force it needs to bend.
0:27:05 > 0:27:08So the less likely it is to crack.
0:27:10 > 0:27:13And in such a fine thread, drawn from molten glass,
0:27:13 > 0:27:17there's less chance of a defect, which could make it shatter.
0:27:20 > 0:27:24That's not the only thing that's special about this glass.
0:27:24 > 0:27:29It's also incredibly pure, so light can travel down it for miles.
0:27:31 > 0:27:34But light normally travels in straight lines,
0:27:34 > 0:27:36so how does it go around these bends?
0:27:38 > 0:27:41'To find out, I'm with Dr Natalie Wheeler,
0:27:41 > 0:27:45'who researches optical fibres at the University of Southampton.'
0:27:45 > 0:27:48So here we have a length of optical fibre, and as you can see,
0:27:48 > 0:27:52it's extremely thin, and also, since it's been coated with
0:27:52 > 0:27:55a polymer during the fabrication process, it's also extremely strong.
0:27:55 > 0:28:01Inside the coating of this optical fibre is a glass core,
0:28:01 > 0:28:04surrounded by a glass cladding layer.
0:28:04 > 0:28:08It's these two layers that help the light go around bends.
0:28:08 > 0:28:12We can actually demonstrate how this works using this set up here.
0:28:12 > 0:28:16- If you would like to just pull out that cork there.- This one?- Yeah.
0:28:17 > 0:28:22Wow! That's amazing! Look at that!
0:28:23 > 0:28:27'This laser light mimics what happens in an optical fibre.
0:28:29 > 0:28:32'When light travels from a dense to a less dense medium,
0:28:32 > 0:28:34'like this liquid to air,
0:28:34 > 0:28:37'or from the glass core to its cladding layer,
0:28:37 > 0:28:43'what happens to the light depends on the angle at which it hits the boundary.
0:28:43 > 0:28:46'If the angle is large enough, it won't pass through.
0:28:46 > 0:28:48'It'll be reflected back in.'
0:28:48 > 0:28:52At the interface between the two materials,
0:28:52 > 0:28:55the light is being reflected, and you can see it bouncing along here.
0:28:55 > 0:29:00So the interface between them allows the total internal reflection?
0:29:00 > 0:29:03- Exactly.- That's absolutely fantastic.
0:29:03 > 0:29:08Using these amazing properties of optical fibres, in 1930,
0:29:08 > 0:29:11medical student, Heinrich Lamm, successfully transmitted
0:29:11 > 0:29:15the first image of a lightbulb filament using an optical fibre bundle.
0:29:17 > 0:29:22Then scientists realised they could have a far more powerful use -
0:29:22 > 0:29:27to transmit vast amounts of information at the speed of light.
0:29:32 > 0:29:35Optical fibres have become a foundation
0:29:35 > 0:29:37of the information revolution.
0:29:40 > 0:29:43Without them, we wouldn't have our world of instant phone calls,
0:29:43 > 0:29:46e-mails, cable TV or the internet.
0:29:48 > 0:29:52Today, a single strand of optical fibre can transmit
0:29:52 > 0:29:572.5 million times more information than a standard copper cable.
0:29:57 > 0:30:00In fact, over the last 50 years,
0:30:00 > 0:30:03ceramics have been taking over from metals
0:30:03 > 0:30:06in a materials revolution that gave us our high-tech, high speed world.
0:30:06 > 0:30:11Ceramics have also been replacing metals
0:30:11 > 0:30:13in medicine and in electronics.
0:30:15 > 0:30:19But there's one essential of life that surely metals are vital for -
0:30:19 > 0:30:20electricity.
0:30:23 > 0:30:29Electricity travels down miles and miles of metal wires to reach us.
0:30:29 > 0:30:31And because of the way metals conduct,
0:30:31 > 0:30:34some of the energy is lost along the way.
0:30:35 > 0:30:40If I make a small electric circuit with some copper wire,
0:30:40 > 0:30:43a battery and a bulb, the bulb burns
0:30:43 > 0:30:46pretty brightly, but now, if I just use a longer wire,
0:30:46 > 0:30:5165 metres of it, same bulb, same battery,
0:30:51 > 0:30:53it's much duller.
0:30:53 > 0:30:57So the wire absorbs quite a lot of the electricity.
0:30:57 > 0:31:00So when it comes to crossing countries and continents,
0:31:00 > 0:31:03we lose a massive amount of energy.
0:31:03 > 0:31:06The UK's electricity network loses more than 7% of the electricity
0:31:06 > 0:31:09just getting from the power station to your plug.
0:31:12 > 0:31:15But that could change and it's all down to the way
0:31:15 > 0:31:19some materials respond to extreme temperatures.
0:31:21 > 0:31:24This time, the transformation isn't due to the power of heat,
0:31:24 > 0:31:27but of cold.
0:31:31 > 0:31:35In 1911, Dutch physicist Heike Kamerlingh Onnes
0:31:35 > 0:31:39was testing materials at extremely low temperatures.
0:31:40 > 0:31:45He cooled mercury down to the temperature of liquid helium.
0:31:45 > 0:31:48Minus 269 degrees Celsius.
0:31:48 > 0:31:52That's just four degrees above absolute zero.
0:31:54 > 0:31:58Onnes discovered something that nobody had ever seen before.
0:31:58 > 0:32:00At these extreme temperatures,
0:32:00 > 0:32:04mercury conducts electricity without losing any energy at all.
0:32:04 > 0:32:07He called it superconductivity.
0:32:11 > 0:32:17In a metal, electricity is conducted when electrons travel through it.
0:32:17 > 0:32:19At normal temperatures,
0:32:19 > 0:32:23the electrons bump into atoms and lose energy.
0:32:23 > 0:32:25It's called electrical resistance.
0:32:27 > 0:32:32But at extremely low temperatures, the electrons can pair up and
0:32:32 > 0:32:37navigate through the atoms without bumping into them and losing energy.
0:32:37 > 0:32:40The metal now has no electrical resistance.
0:32:44 > 0:32:48Onnes received a Nobel Prize for his work.
0:32:48 > 0:32:51And in the years that followed, scientists discovered
0:32:51 > 0:32:56that many other metals become superconductors at temperatures close to absolute zero.
0:32:59 > 0:33:01With society depending more and more on electricity,
0:33:01 > 0:33:05superconductors seem to have a huge potential.
0:33:05 > 0:33:08But the breakthrough was as frustrating as it was exciting.
0:33:08 > 0:33:12How could we find a use for something that only worked at such extreme temperatures?
0:33:13 > 0:33:19What was needed was a material that would perform like the superconducting metals,
0:33:19 > 0:33:23but at a temperature that wasn't down near absolute zero.
0:33:26 > 0:33:29And when the breakthrough came, it wasn't the material
0:33:29 > 0:33:32that anyone expected to conduct electricity at all.
0:33:32 > 0:33:35It wasn't a metal. It was a ceramic.
0:33:35 > 0:33:39This is a ceramic called yttrium barium copper oxide,
0:33:39 > 0:33:42and not only does it not conduct electricity, it doesn't
0:33:42 > 0:33:46really behave very interestingly at all to electricity or magnets.
0:33:48 > 0:33:53It seems dead. But cold does many strange things to this material.
0:33:53 > 0:33:55If we cool it down
0:33:55 > 0:33:58and, admittedly, we have to cool it down quite a lot,
0:33:58 > 0:34:03to liquid nitrogen temperatures, that's minus 196 degrees centigrade.
0:34:08 > 0:34:12It takes a few minutes for the liquid nitrogen to cool it right down,
0:34:12 > 0:34:17and when it does, the ceramic becomes a superconductor.
0:34:17 > 0:34:20And it has another trick up its sleeve.
0:34:21 > 0:34:23Now when I place a magnet over the ceramic,
0:34:23 > 0:34:25something completely different happens.
0:34:28 > 0:34:30It seems like the magnet floats on air.
0:34:30 > 0:34:33What's happening is it is being levitated by the ceramic.
0:34:33 > 0:34:36The ceramic is repelling the magnetic field of the magnet.
0:34:36 > 0:34:39It's absolutely extraordinary.
0:34:41 > 0:34:45The cold has changed the way the ceramic behaves.
0:34:45 > 0:34:49It's showing another material miracle
0:34:49 > 0:34:52that's unique to superconductors.
0:34:52 > 0:34:57Normally, this ceramic isn't affected at all by a magnet.
0:34:58 > 0:35:02But when the ceramic is cooled, and becomes a superconductor,
0:35:02 > 0:35:08an external magnetic field makes electrical currents flow within it.
0:35:08 > 0:35:11These generate their own magnetic field
0:35:11 > 0:35:13which repels the external one.
0:35:17 > 0:35:21And so a ceramic can repel a magnet.
0:35:21 > 0:35:25This ceramic has now become a superconductor and that means
0:35:25 > 0:35:28it can conduct electricity without losing any energy.
0:35:28 > 0:35:33It can do that when it's cooled to about minus 196 degrees centigrade.
0:35:33 > 0:35:36That may sound extreme, but it's pretty warm compared
0:35:36 > 0:35:39to the temperatures you need to make metals superconduct.
0:35:39 > 0:35:42Since they discovered this,
0:35:42 > 0:35:46scientists have begun to design ceramics at the atomic level.
0:35:46 > 0:35:50They've added different elements, atom by atom,
0:35:50 > 0:35:51in search of their ultimate aim.
0:35:53 > 0:35:57Superconductors that will work at practical temperatures.
0:36:01 > 0:36:03Degree by degree, we're approaching our goal.
0:36:03 > 0:36:07We currently use this thick copper cable to transmit electricity.
0:36:07 > 0:36:11But it can now be replaced by this thin superconducting ceramic cable.
0:36:11 > 0:36:15And as long as it's cooled, it will lose no electricity.
0:36:17 > 0:36:20In America, ceramic superconductors
0:36:20 > 0:36:22have started to be used in the power grid.
0:36:24 > 0:36:28China and Korea are planning to use them in cities of the future.
0:36:32 > 0:36:37In years to come, they could transport electricity on a massive scale.
0:36:39 > 0:36:43Just imagine, solar farms in the desert could be supplying
0:36:43 > 0:36:48our homes in Britain with minimal energy being lost on the way.
0:36:52 > 0:36:54By pushing metals and ceramics to their very limits,
0:36:54 > 0:36:59we've built vast cities that have changed the face of the planet.
0:36:59 > 0:37:02We've conquered land, sea and air.
0:37:02 > 0:37:06And we've learnt to communicate at the speed of light.
0:37:08 > 0:37:12But I think the materials that are perhaps our greatest achievement
0:37:12 > 0:37:16are something entirely artificial, invented by us,
0:37:16 > 0:37:19and created in the lab -
0:37:19 > 0:37:21plastics.
0:37:21 > 0:37:24It's not just technologically marvellous stuff.
0:37:24 > 0:37:27It's fundamentally changed how we live.
0:37:27 > 0:37:29It's allowed us to be modern.
0:37:29 > 0:37:32I'm going to explore how we turned our backs
0:37:32 > 0:37:37on the raw materials of nature and began to design and create our own.
0:37:37 > 0:37:42Plastic - better, cheaper, and entirely man-made.
0:37:42 > 0:37:45We've created more new materials in the last 100 years
0:37:45 > 0:37:49than in the rest of history, and what's really exciting about that
0:37:49 > 0:37:51is that it's just the beginning.
0:37:51 > 0:37:54We're on the verge of creating a new generation of materials
0:37:54 > 0:37:56more ambitious than ever before.
0:37:58 > 0:38:01And that's because we are coming full circle
0:38:01 > 0:38:04and making new materials that are completely artificial,
0:38:04 > 0:38:08but which take their inspiration from the natural world.
0:38:15 > 0:38:20The story began in 1834, in a prison in Philadelphia
0:38:20 > 0:38:22with one inmate who saw the potential
0:38:22 > 0:38:25of a newly imported natural material.
0:38:26 > 0:38:29His name was Charles Goodyear,
0:38:29 > 0:38:32and he'd been locked up for not paying his debts.
0:38:32 > 0:38:35But Goodyear wasn't making his supper,
0:38:35 > 0:38:38he was cooking up something entirely different.
0:38:43 > 0:38:47Goodyear was obsessed with this stuff, natural rubber.
0:38:47 > 0:38:49It was the miracle substance of the early 19th century
0:38:49 > 0:38:52because it had some very strange properties.
0:38:52 > 0:38:55It was stretchy but it was also waterproof.
0:38:55 > 0:38:58And this meant that it seemed to have huge potential to make things
0:38:58 > 0:39:02like raincoats, tyres and wellies.
0:39:02 > 0:39:05If, however, it wasn't for one thing.
0:39:07 > 0:39:09This is a ball of natural rubber...
0:39:11 > 0:39:13..and you can see that at room temperature
0:39:13 > 0:39:14it's pretty lively stuff.
0:39:15 > 0:39:17But if you change the temperature,
0:39:17 > 0:39:21well then, the material changes its behaviour.
0:39:21 > 0:39:25So look, I've got some different types of temperature here.
0:39:25 > 0:39:27I've got a ball that's been cooled down.
0:39:27 > 0:39:29And here it is.
0:39:29 > 0:39:30And let's see how that behaves.
0:39:32 > 0:39:36It's quite ridiculously dead, inert.
0:39:36 > 0:39:39None of that springiness. None of that liveliness is left.
0:39:39 > 0:39:42And what about the hot one?
0:39:45 > 0:39:48It's funny, you only have to heat it up a little bit
0:39:48 > 0:39:50and it becomes really pongy and also sticky.
0:39:50 > 0:39:55Almost disgusting. It's a very unpleasant material to be around.
0:39:55 > 0:39:57In Goodyear's day, people noticed this
0:39:57 > 0:40:00and products made out of natural rubber
0:40:00 > 0:40:02were pretty hopeless in the hot or the cold weather.
0:40:02 > 0:40:07Shops that sold them, well, they were inundated with complaints.
0:40:07 > 0:40:10So this is the problem that Goodyear was trying to solve.
0:40:13 > 0:40:17Goodyear was determined to find the magic ingredients
0:40:17 > 0:40:21that would improve rubber and transform it into a material
0:40:21 > 0:40:26that didn't melt in the heat or go hard in the cold.
0:40:26 > 0:40:30He tried mixing rubber with the most bizarre substances imaginable,
0:40:30 > 0:40:35from black ink to witch hazel to chicken soup!
0:40:35 > 0:40:38But nothing seemed to work.
0:40:44 > 0:40:47But his luck was to change.
0:40:52 > 0:40:56In 1839, having been bailed out of debtor's prison,
0:40:56 > 0:41:01Goodyear found himself at a small rubber company in Massachusetts.
0:41:03 > 0:41:06Dr Stuart Cook is director of research
0:41:06 > 0:41:10at the Malaysian Rubber Board's UK research centre
0:41:10 > 0:41:13and is going to help us recreate what Goodyear did.
0:41:15 > 0:41:18That counts as one of the weirdest things I've ever seen.
0:41:18 > 0:41:22Goodyear was still trying anything he could lay his hands on.
0:41:22 > 0:41:24And this time,
0:41:24 > 0:41:28he tried adding two substances to the natural rubber,
0:41:28 > 0:41:30yellow sulphur and white lead,
0:41:30 > 0:41:33which was commonly used as a pigment.
0:41:35 > 0:41:38Using the factory's mill, these were ground into the natural rubber
0:41:38 > 0:41:41until they were both thoroughly mixed in.
0:41:43 > 0:41:45So you can see now the rubber compound
0:41:45 > 0:41:47has changed quite dramatically.
0:41:47 > 0:41:50Yes. It's looking extremely voluptuous, actually.
0:41:50 > 0:41:53- It's got this creaminess about it.- Yes.
0:41:55 > 0:41:59So far, there were no signs that Goodyear was any closer
0:41:59 > 0:42:03to reaching his goal of improving on natural rubber.
0:42:05 > 0:42:09The rubber compound that came out of the mill
0:42:09 > 0:42:12appeared no better than previous attempts.
0:42:12 > 0:42:15Stuart, I have to say it is sticky.
0:42:15 > 0:42:17I mean, he must have been pretty disappointed
0:42:17 > 0:42:20because he's trying to solve the stickiness problem, and it's sticky.
0:42:20 > 0:42:23The crucial thing is what happened next.
0:42:24 > 0:42:26Whether by mistake or not,
0:42:26 > 0:42:30Goodyear left the rubber compound lying on a hot stove.
0:42:30 > 0:42:35Natural rubber would have melted into a gooey mess,
0:42:35 > 0:42:39but Goodyear's rubber compound didn't do this.
0:42:39 > 0:42:42The combination of sulphur, white lead and heat
0:42:42 > 0:42:46had transformed the rubber into a very different material.
0:42:48 > 0:42:52That is absolutely extraordinary. What an amazing material.
0:42:54 > 0:42:57So Goodyear, when he referred to this,
0:42:57 > 0:42:59said it had the appearance of looking charred.
0:42:59 > 0:43:03It's better than charred, I think he was under-estimating that!
0:43:03 > 0:43:06And it's not sticky.
0:43:09 > 0:43:10Cured, as Goodyear said.
0:43:16 > 0:43:20This is what the surface of natural rubber looks like
0:43:20 > 0:43:23magnified over 10,000 times.
0:43:23 > 0:43:26It's an irregular structure with stretched-out fibres
0:43:26 > 0:43:28interspersed with tiny air pockets.
0:43:31 > 0:43:34By a process which became known as vulcanisation,
0:43:34 > 0:43:39Goodyear had transformed this to make it useful to man.
0:43:39 > 0:43:43The key to that change is what happens inside the rubber.
0:43:48 > 0:43:52Natural rubber is made up of lots of long strands.
0:43:52 > 0:43:56Each one, a single molecule made of atoms.
0:43:57 > 0:44:01During vulcanisation, the sulphur creates links between the molecules.
0:44:01 > 0:44:04This is what makes rubber tougher
0:44:04 > 0:44:07and able to withstand hot or cold temperatures.
0:44:13 > 0:44:15So he must have been a very happy man?
0:44:15 > 0:44:19I think he realised the importance of this chance discovery.
0:44:20 > 0:44:24But it took him then many years to convince the rest of the world.
0:44:24 > 0:44:27But this was really the start of the rubber industry as we know it.
0:44:30 > 0:44:34The significance of Goodyear's discovery went far beyond rubber.
0:44:34 > 0:44:36What he showed was the power of chemistry
0:44:36 > 0:44:39to transform raw materials into something new.
0:44:39 > 0:44:42What he'd discovered was still called rubber
0:44:42 > 0:44:44but it didn't occur naturally.
0:44:44 > 0:44:45It was man-made.
0:44:48 > 0:44:53The success of rubber kick-started a quest for more man-made materials
0:44:53 > 0:44:56to better nature's own.
0:44:56 > 0:45:00This led to the discovery of the first commercially-produced plastic.
0:45:00 > 0:45:05And no-one was more aware of its potential than Dr Leo Baekeland.
0:45:09 > 0:45:13In his mansion in the suburbs of New York, he set to work.
0:45:16 > 0:45:19He'd set his sights on replacing shellac
0:45:19 > 0:45:22which is the material that old records were made out of.
0:45:22 > 0:45:26Shellac is a resin that's excreted by the Indian lac beetle,
0:45:26 > 0:45:27and it looks like this!
0:45:27 > 0:45:29And as the demand for shellac increased,
0:45:29 > 0:45:31the lac beetle just couldn't keep up.
0:45:31 > 0:45:34And Baekeland thought that he could solve this problem
0:45:34 > 0:45:37by creating a new plastic.
0:45:40 > 0:45:44In the grounds of his estate, Baekeland had built a chemistry lab
0:45:44 > 0:45:47equipped with everything he would need.
0:45:56 > 0:45:58Baekeland's starting point
0:45:58 > 0:46:00was to investigate a mysterious chemical reaction.
0:46:00 > 0:46:05It involves mixing two chemicals, phenol and formaldehyde.
0:46:07 > 0:46:12Dr Sara Ronca is a chemist at Loughborough University
0:46:12 > 0:46:15and is an expert in plastics.
0:46:15 > 0:46:17This is quite a pongy reaction you've got here.
0:46:17 > 0:46:18It's a very smelly one!
0:46:20 > 0:46:25This is the reaction that interested Baekeland.
0:46:25 > 0:46:28It takes a few minutes before anything happens...
0:46:29 > 0:46:31He must have been a patient man, Baekeland?
0:46:31 > 0:46:33You really need a lot of patience.
0:46:35 > 0:46:39..but then, something rather spectacular occurs.
0:46:39 > 0:46:43- Oh! Woah.- Yeah.
0:46:43 > 0:46:46The reaction creates a plastic-y substance
0:46:46 > 0:46:48that moulds to the shape of the beaker,
0:46:48 > 0:46:49and turns pink.
0:46:49 > 0:46:52Nobody had yet found a use for it.
0:46:52 > 0:46:55But it caught the attention of Baekeland.
0:46:55 > 0:46:58Look it, though. It's pretty cool stuff!
0:46:58 > 0:47:02It does look promising, I can see why he's interested in it.
0:47:02 > 0:47:05It's sort of plasticy, but it falls apart.
0:47:05 > 0:47:08It falls apart and it's porous, so you cannot really use it.
0:47:10 > 0:47:13Baekeland understood that if he managed to get
0:47:13 > 0:47:16a better version of this material, this could have some potential.
0:47:19 > 0:47:22Baekeland believed he could find a way
0:47:22 > 0:47:24to modify the chemical reaction
0:47:24 > 0:47:28so it would give him a better, stronger, more useful plastic.
0:47:28 > 0:47:32Day after day, he tried everything he could think of.
0:47:32 > 0:47:37After five years of painstaking work,
0:47:37 > 0:47:42he finally found that by controlling the speed of the reaction
0:47:42 > 0:47:46with chemicals and heat, he could produce something different and new.
0:47:47 > 0:47:51This time, there was no pink solid produced.
0:47:51 > 0:47:56Instead, inside the flask an orange resin was slowly forming.
0:47:56 > 0:47:59Let's have a look. It looks...
0:47:59 > 0:48:00It's like honey.
0:48:00 > 0:48:03It's very very viscous. Exactly like honey.
0:48:04 > 0:48:09Baekeland's next step was to pour the liquid resin into a mould.
0:48:11 > 0:48:14With pressure and heat,
0:48:14 > 0:48:17he hoped it would turn into a solid plastic shape.
0:48:20 > 0:48:24In our case, we're trying to make a plastic cup.
0:48:25 > 0:48:28So either this is going to be a soggy mess or...
0:48:28 > 0:48:30Let's see what we managed to achieve.
0:48:32 > 0:48:34Oh. Aw.
0:48:34 > 0:48:38Well, I don't think this is quite what we were expecting to produce!
0:48:38 > 0:48:39What do you think went wrong?
0:48:39 > 0:48:43I guess we didn't wait long enough.
0:48:43 > 0:48:47We still have some bubbles in it.
0:48:47 > 0:48:49But you can see the shape.
0:48:49 > 0:48:53Can you imagine how many times Baekeland had to repeat this
0:48:53 > 0:48:55to get something nice?
0:48:55 > 0:48:58I think for me, you see modern plastic objects
0:48:58 > 0:49:01in their perfect thousands, millions of them.
0:49:01 > 0:49:04When you actually try to make one yourself,
0:49:04 > 0:49:07you realise it's really tricky stuff.
0:49:08 > 0:49:10Baekeland persisted
0:49:10 > 0:49:15until he had perfected the process to make hard, solid plastic objects.
0:49:15 > 0:49:19And he named his new plastic Bakelite.
0:49:21 > 0:49:25As a liquid resin, Bakelite is made up of stringy chains
0:49:25 > 0:49:29that can move around, so it can be moulded.
0:49:29 > 0:49:32But when heat and pressure are applied,
0:49:32 > 0:49:36the chains grow in length, links form between them,
0:49:36 > 0:49:38locking Bakelite into shape.
0:49:40 > 0:49:44Bakelite was a major breakthrough.
0:49:44 > 0:49:49By the end of 1930s, over 200,000 tonnes of Bakelite
0:49:49 > 0:49:53had been made into a fantastic variety of household objects.
0:49:55 > 0:50:00But as successful as it was, even Bakelite had its limits.
0:50:00 > 0:50:04What strikes you is not just what's here, but what's missing.
0:50:04 > 0:50:07There are no plastic bags, there are no water bottles,
0:50:07 > 0:50:09there are no trainers,
0:50:09 > 0:50:13these objects that form such a large part of our lives.
0:50:13 > 0:50:17And that's because Bakelite is just not up to making those things.
0:50:17 > 0:50:20It's too hard and brittle. It's inflexible.
0:50:20 > 0:50:23This material of a thousand uses,
0:50:23 > 0:50:26never became as ubiquitous as the plastics we use today.
0:50:32 > 0:50:34But that was about to change.
0:50:34 > 0:50:38Factories would soon be churning out countless new plastics
0:50:38 > 0:50:40that would transform our lives.
0:50:42 > 0:50:45They weren't invented by chance or trial and error,
0:50:45 > 0:50:46but for the first time
0:50:46 > 0:50:50through an understanding of the inner structure of plastics.
0:50:54 > 0:50:58Plastics are polymers and that's Greek for many parts.
0:50:58 > 0:51:01So they're a bit like this chain of paperclips.
0:51:01 > 0:51:05They're individual components linked together.
0:51:07 > 0:51:10Although in the case of plastics, the individual components
0:51:10 > 0:51:13are molecules containing mostly carbon and hydrogen.
0:51:14 > 0:51:19And the key thing is that they can join together to form long chains.
0:51:21 > 0:51:23Now in the 1920s, when scientists realised
0:51:23 > 0:51:26this is what plastics looked like,
0:51:26 > 0:51:30it opened up new possibilities for making plastics.
0:51:30 > 0:51:31Because before then, well,
0:51:31 > 0:51:35the chemical reactions they were using were a bit of a mystery.
0:51:35 > 0:51:38But then they realised that they only had to find molecules
0:51:38 > 0:51:39that would link together
0:51:39 > 0:51:42and they could create loads of new plastics.
0:51:45 > 0:51:47And in one of those great moments in history
0:51:47 > 0:51:51where knowledge and opportunity coincide,
0:51:51 > 0:51:54scientists realised that a vast source of raw ingredients
0:51:54 > 0:51:58for these new plastics had already been discovered.
0:51:59 > 0:52:02With the proliferation of the motorcar
0:52:02 > 0:52:04and expansion of industry and cities,
0:52:04 > 0:52:08enormous quantities of oil and gas were being pumped out of the ground
0:52:08 > 0:52:11and processed into fuel.
0:52:11 > 0:52:15And the products of oil and gas refineries
0:52:15 > 0:52:18were hydrocarbons, containing exactly the kind of molecules
0:52:18 > 0:52:21that could join up to make plastics.
0:52:21 > 0:52:23Cheap and abundant,
0:52:23 > 0:52:27everything was now in place for the plastics explosion.
0:52:28 > 0:52:32Nylon, PVC,
0:52:32 > 0:52:36polystyrene, polyester.
0:52:37 > 0:52:41All destined to become household names.
0:52:44 > 0:52:47Plastics were taking over our material world.
0:52:47 > 0:52:51Everything from toys and tools to footwear and furniture
0:52:51 > 0:52:53could now be made with plastics.
0:52:53 > 0:52:54In every aspect of our lives,
0:52:54 > 0:52:57they were replacing more traditional materials
0:52:57 > 0:53:00like metals and woods, ceramics and leather.
0:53:00 > 0:53:04But there was one area which they couldn't compete,
0:53:04 > 0:53:06and that's where strength was required.
0:53:08 > 0:53:10The modern age demanded strong materials.
0:53:12 > 0:53:14And when we needed strength,
0:53:14 > 0:53:17we looked not to plastics but to metals.
0:53:19 > 0:53:21On their own, plastics were too weak,
0:53:21 > 0:53:25too bendy to make a car or a plane.
0:53:25 > 0:53:29But plastics had one big advantage, they were light,
0:53:29 > 0:53:32an essential quality for speed and flight.
0:53:32 > 0:53:37So scientists set out on a quest to create plastics as strong as metals.
0:53:40 > 0:53:45In 1963, engineers at the Royal Aircraft Establishment
0:53:45 > 0:53:48in Farnborough made a breakthrough.
0:53:48 > 0:53:51They managed to strengthen plastic so effectively,
0:53:51 > 0:53:54it looked as though it might give metal a run for its money.
0:53:58 > 0:54:00This is carbon fibre.
0:54:00 > 0:54:03It's extremely strong, light and stiff.
0:54:03 > 0:54:06Scientists found that when they combined it with plastic
0:54:06 > 0:54:08they created a new material that was much better
0:54:08 > 0:54:10than the sum of its parts.
0:54:11 > 0:54:14Some people called it black plastic,
0:54:14 > 0:54:16but today we know it as carbon fibre composite.
0:54:18 > 0:54:22Here, a carbon fibre composite is being made from sheets
0:54:22 > 0:54:25that contain carbon fibres and plastic.
0:54:27 > 0:54:30It's built up layer by layer,
0:54:30 > 0:54:33on moulds that can take any shape you need.
0:54:33 > 0:54:38And then cooked in an oven, to make the plastic set hard.
0:54:38 > 0:54:43The end result is a material with a unique combination of properties,
0:54:43 > 0:54:46strong, stiff and light.
0:54:46 > 0:54:51Ideal for making one of the fastest machines on the planet.
0:54:56 > 0:54:58Since the 1980s,
0:54:58 > 0:55:01Formula One teams stopped using metal for their car bodies,
0:55:01 > 0:55:04and changed to using carbon fibre composite
0:55:04 > 0:55:06because of its winning combination
0:55:06 > 0:55:09of lightness, stiffness and strength.
0:55:11 > 0:55:13But lightness, stiffness and strength
0:55:13 > 0:55:15aren't all we demand from our materials.
0:55:15 > 0:55:19In recent years, one new material with exotic
0:55:19 > 0:55:23but incredibly useful properties has come out of the lab -
0:55:23 > 0:55:25graphene.
0:55:25 > 0:55:27It's the strongest material we know.
0:55:27 > 0:55:31200 times stronger than steel.
0:55:31 > 0:55:33And in this two-dimensional material,
0:55:33 > 0:55:38electricity travels at an amazing one million metres per second.
0:55:40 > 0:55:44The different colours represent different thicknesses of graphite.
0:55:44 > 0:55:47The yellow is hundreds of atoms thick.
0:55:47 > 0:55:51But the fragment that is faint blue, almost transparent,
0:55:51 > 0:55:54is just one single atomic layer.
0:55:54 > 0:55:57You can't go thinner than this.
0:55:57 > 0:55:59This is who I've come to see.
0:55:59 > 0:56:04Professor Andre Geim is one-half of the Nobel Prize-winning duo
0:56:04 > 0:56:06that discovered graphene.
0:56:06 > 0:56:11Because it shows so remarkable properties, especially conductivity.
0:56:11 > 0:56:14Think about this. This is only atom thick.
0:56:14 > 0:56:17And when you make films thinner and thinner,
0:56:17 > 0:56:20usually properties deteriorate.
0:56:20 > 0:56:23In this, you are at the ultimate limit.
0:56:25 > 0:56:28Magnified 20 million times,
0:56:28 > 0:56:32this is what graphene looks like at the atomic scale.
0:56:34 > 0:56:39Each blurry white spot is an individual carbon atom
0:56:39 > 0:56:45and you can just make out how they are arranged in a hexagonal pattern.
0:56:45 > 0:56:47Graphene is two dimensional
0:56:47 > 0:56:50and that's what gives it its unique properties.
0:56:52 > 0:56:56This material, despite being one atom thick,
0:56:56 > 0:57:01it's already conducting and that was sort of eureka moment
0:57:01 > 0:57:05when I first realised that this material is worth studying.
0:57:09 > 0:57:13In the hi-tech, dust-free clean labs at Manchester,
0:57:13 > 0:57:17Andre's team are developing transistors made from graphene.
0:57:18 > 0:57:22Graphene could ultimately replace silicon chips,
0:57:22 > 0:57:25creating the next generation of super-fast computers,
0:57:25 > 0:57:29up to 100 times faster than today's.
0:57:29 > 0:57:33And we're only just beginning to imagine the vast possibilities
0:57:33 > 0:57:38graphene opens up in other fields of science.
0:57:38 > 0:57:41There's a sense in which anything is possible,
0:57:41 > 0:57:44that only our imaginations will limit what we can create.
0:57:51 > 0:57:53We've come a long way since we smelted copper
0:57:53 > 0:57:56from the rocks of the desert.
0:57:56 > 0:57:59We've manipulated, moulded and manufactured materials
0:57:59 > 0:58:02that have allowed us to shape our modern world
0:58:02 > 0:58:04and create magnificent structures like these.
0:58:04 > 0:58:08But for me, there's no doubt that the journey is far from over.
0:58:08 > 0:58:10There are new discoveries to be made,
0:58:10 > 0:58:12frontiers to be crossed.
0:58:12 > 0:58:18The inner world of material science holds much of the key to our future.