Episode 5 Wonderstuff


Episode 5

Series exploring the wonder in ordinary things. Jane Moore investigates the stickiness of household essentials, including super-strength glues, paint and non-stick frying pans.


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Transcript


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This series is about the stuff we just can't live without.

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The cleaners, the cosmetics,

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the convenience items that we use every single day.

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How do these things actually work?

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'I'm Jane Moore and I've set out to discover the hidden science

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'in all those household essentials we simply take for granted.

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'My journey will put me to the test in the most unusual places...'

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Ta-da!

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We have made toothpaste!

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'..change the way I think about science...'

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That is utterly astonishing.

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'..and let me see myself in a whole new light.'

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Yes, take a product, any product, and chuck away the packaging.

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We're not interested in that because this series is about what's inside.

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My task is to find out which ingredients do the clever work

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and where those ingredients come from.

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'Welcome to the extraordinary hidden world of Wonderstuff.'

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'So far, I've been on an eye-opening trip

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'around some of Britain's most cutting-edge institutions

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'that dream up some of those lotions and potions

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'that help make our daily domestic lives so much easier.'

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But my Wonderstuff tour doesn't end there.

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No, the next stop - to stick or not to stick.

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That's the new question that's keeping me awake at night.

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'So, to help me sleep better, I want to get to the bottom of glue,

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'non-stick pans and paint.

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'Later in the show, my master of materials,

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'Dr Mark Miodownik, will be luring me deep into the unknown.'

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It's like Raiders Of The Lost Ark down here.

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'Before then, I'm off to get the low-down

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'on something that really does hold our lives together.'

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I'm on the trail of what makes things stick

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and, call me predictable, but to my mind,

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there's only one place to start - glue.

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Breakages in the home are a real pain,

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not helped by the fact that choosing the right glue

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is no simple matter.

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The choices available seem endless,

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but are all these glues really that different

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and is there a Wonderstuff that makes one particular type of glue

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the daddy of them all?

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To find out how glue works,

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I'm off to Cambridge to meet Dr Ewen Kellar,

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principle project leader at TWI,

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who advise everyone from the Ministry of Defence

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to Formula One about the right ways to stick stuff together.

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But despite all these high-tech applications,

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Ewen reckons the simplest way to understand glue

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is to start where the ancient Egyptians did -

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using milk, with a sticking power we've all seen in action.

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Glue made from milk has been around for many thousands of years.

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It's called casein. The name comes from the protein -

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the actual whiteness in the milk is casein.

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'If you fancy trying this at home, use skimmed milk

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'and curdle it by adding vinegar.'

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I don't know if you can see that, but it's become all rather lumpy.

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-It looks like the milk you find in a student's fridge.

-Yeah.

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'Ewen then filters the mixture to get just the protein.'

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So, what we now want to do is we want to basically

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put this back into some sort of solution.

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So, this is bicarbonate of soda, baking soda.

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'Adding bicarb apparently neutralises the vinegar

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'and forces the milk proteins to stick together.'

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Little molecules join together, one after the other,

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and form very long chains.

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'Then, just add water and voila!'

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If we leave this now, for a few minutes,

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it will settle down into an almost clear liquid

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which can then be used as a glue.

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This has been used to bond wood.

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It was used to bond furniture in Egyptian times.

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'You can also get natural glues from wheat, honey and cheese.'

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I'm impressed by that.

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I never knew you could actually just make glue from the stuff

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that you find in your kitchen.

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'Apparently, all modern glues use the same principle we've seen here

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'called polymerization,

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'where molecules form long chains that bind things together.

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'So, why are there so many different types of glue?

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'Ewen wants to show me how modern glues work best

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'when they're tailored to work on specific surfaces

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'and he's starting with a wood glue.'

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-So, that's the joint of the two bits of wood, yeah?

-Yes.

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What we do is we basically put this in the machine

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which we see in front of us and we pull it apart.

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'A simple wood glue joint can hold together under enormous strain.'

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So, we're now at 270 kilos.

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That's several of me dangling off the end of this little bit of wood.

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Poor thing!

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'But try the same wood glue on metal and it's a different matter.'

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Here, we've got ten kilograms. The joint is virtually failed.

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I'm going to look really strong.

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Yay! Look at that!

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So, it genuinely is that there are glues that work better

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-on a specific surface?

-Definitely.

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'OK, but is there a gluey Wonderstuff?

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'Something that could bond absolutely anything?

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'I'm wondering about what's in those little tubes

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'of instant super-strength glue like I use at home.'

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And what is this? It's cyanoacrylate.

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Yes, cyanoacrylate. It's basically the chemical name of these materials.

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So, basically, here, you've got very small molecules

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which combine together when you put them in contact with moisture.

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They go from being very, very runny

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to very, very viscous very, very quickly

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and ultimately go hard cos they entangle and lock together.

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But it happens incredibly fast - only a few seconds.

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Which is what makes it user-friendly because you want it to act fast.

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'Cyanoacrylate got its super reputation as a fast-acting adhesive

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'on the battlefields of Vietnam.

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'To show me how, Ewen's demonstrating with some pork.'

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Here's a cut. So, basically, what the doctor would do

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would be just literally lightly apply the adhesive

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on the outside of the cut.

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Imagine in a real situation, this wound may well be bleeding,

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so the adhesive's got a bit of a tough job to do.

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The cyanoacrylate is good at coagulating the blood

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and stopping bleeding.

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Then, all you would do - you would hold it together, like this.

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So, no stitches, just a straightforward bond.

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Much, much quicker, much, much less painful than otherwise.

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-That has really worked, hasn't it?

-Yeah.

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'And now, medics do this with a sterile version

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'on our day-to-day wounds.

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'Fast-setting, super-strength cyanoacrylate

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'certainly sounds worthy of being a Wonderstuff.

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'But Ewen's got something he reckons is even better -

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'epoxy resin.'

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Cos it's so versatile, you know, you can use it virtually anywhere.

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The main thing to note, really, is there are two parts.

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You'll want to mix these two parts together.

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So, chemically, what is in each tube that causes that reaction?

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Right, well, on one side, we've got a hardener.

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On the other side, we've got what's called a resin.

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So, the resin is like the long polymeric part -

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that's like long chains of spaghetti,

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which is very, very sticky molecules.

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The hardener on the other side has essentially...

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Has the ability to join one chain of spaghetti to the other,

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like rungs on a ladder to form like a cross-link network.

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So it solidifies it in that way.

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'Sounds impressive,

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'but I'm still siding with my cyanoacrylate superglue.

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'So, the only way to decide which one's going to be my Wonderstuff

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'is a head-to-head.'

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Wow! Now, this is what I call a weight!

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'We're putting them to the ultimate strength test-

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'to lift a bag of sand weighing nearly a tonne.'

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OK. Well, let's give the old super-strength glue a test, then.

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'This is the equivalent of sticking a small car to the ceiling

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'with a square inch of glue

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'and the power of my cyanoacrylate has actually got Ewen worried.'

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So, it's taking a load, now.

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I don't believe it!

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Cor, blimey! Did it come off the ground?

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-It did come off the ground...

-Yeah, a little bit.

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..for a nano-second.

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It's a good job I've got a strong heart, isn't it?

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'But can Ewen's poxy little epoxy resin beat that?'

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Maestro, lift!

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-Judging by the big bang last time, I'm standing well back.

-You're not going to get up close?

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No. Too right I'm not.

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OK.

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It's starting to lift off the floor.

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Look at that!

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Well lifted off the floor, that is.

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So, if you really wanted, we could lift this really high

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-and you could stand underneath it, if you wanted.

-Yeah.

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Thank you very much. My days in the circus are long over. Thank you.

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It's absolutely holding steadfast, though, isn't it?

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'I'm not always so gracious in defeat,

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'but it's a clear victory for epoxy resin.

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'No wonder this glue turns up in high places.'

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-Is that an aeroplane wing?

-Yeah.

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-You can't glue an aeroplane wing on, can you?

-Yes, you can.

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In fact, it's actually starting to happen, now.

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Glue's coming back, now, to being used more and more,

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especially with more modern materials which...

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It's difficult to know how else to join them together.

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I mean, even down to the fact that your brake pads are all glued on.

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So, you're trusting your life every day, every time you brake, to glue.

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Ewen, I'm getting the train home, or are they glued as well?

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Quite a lot of them are, yeah.

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'In fact, epoxy resin is so reliable,

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'we use it in the construction of aircraft, cars,

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'boats, golf clubs, skis and snowboards.

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'In fact, anywhere where super high-strength bonds are required,

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'and epoxy glues can stick wood, metal, glass, stone and plastic.

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'A Wonderstuff indeed.

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'Ewen said that glue's brilliance lies in it being a polymer,

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'but what exactly is a polymer?

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'Materials scientist Mark's been raiding his stationery cupboard

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'in order to explain what he reckons

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'are some of our most marvellous molecules.'

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Hello, strange little man on park bench.

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-Fancy seeing you here.

-Just having a sit down and a think.

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What's all this about?

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You've been talking about glue.

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There are examples of things called polymers,

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which is sort of man's attempt to kind of

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recreate the wonderful range of materials that nature can create.

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These soft, flexible materials that repel water

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and can stick to things or not stick to them.

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All of that kind of thing that we see in nature all around us.

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'Silk, starch, cotton, asbestos and DNA are natural polymers,

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'all built from chains of carbon-containing molecules,

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'known as monomers.'

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Add the monomers together to make these different length molecules.

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'Joining together and repeating these same molecules

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'is what creates a polymer.'

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So, a polymer isn't a chemical, as such.

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-It's a sort of... A molecular structure.

-Yes.

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Polymer is a category of material in the same way that metals are.

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'But why is making chains of molecules so useful?'

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By varying the length of the chain, how many units you put together,

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you can make something become harder and harder. That's cool.

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'Just like I saw in glue.

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'Mark tells me that the behaviour of polymers

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'is crucial in explaining the science

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'of something that does the exact opposite of sticking -

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'non-stick.

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'In the kitchen, I'd be hard pushed to think of an invention

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'that's more useful than non-stick.

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'I have no idea what's on my pans,

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'so it means my sausages stay unstuck.

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'So I'm off to try and find out what sort of wonder material

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'could have such a spotless reputation.

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'To show me, know-it-all Mark has dragged me down the hill

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'to the Millennium Dome?!'

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-What are we doing here?

-We're at one of the most amazing buildings in London.

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Look at this. Magnificent, isn't it?

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Well, yes, it's a magnificent structure,

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-but what's that got to do with why we're here?

-PTFE in that roof.

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Look, this is the stuff. Again.

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Blimey! I thought that would be like a ping-pong ball

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-and it's really heavy.

-Heavier than you think.

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Yeah, it's really tough, isn't it?

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'It turns out that PTFE is a fancy kind of plastic.

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'Another one of those clever polymers, by the way,

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'and because it has an extraordinary trick up its sleeve,

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'it can be found on both the roof of the Millennium Dome

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'and inside my frying pan.'

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It's the slipperiest material in the world.

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Nothing sticks to this stuff.

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Even geckos, which can climb up anything at all,

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cannot climb up PTFE.

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It's so slippery that all the dust slides off it.

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-And the bird poo?

-And the bird poo, yes.

-Handily.

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-So, it's 600,000 square feet of PTFE.

-Wow!

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That's a lot of frying pans.

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-It is. How many frying pans is that? Let's calculate it.

-Let's not.

-OK.

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'We rely on PTFE's super slipperiness

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'for all sorts of other essential jobs, too.'

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Famously, the astronauts who walked on the moon

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had PTFE coated inside their space suits

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because when they're moving about in space,

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they can't have friction on the inside

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which might cause a little hole to form cos then, they would die.

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It's starting to be used inside the body.

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So, like an artificial hip.

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Cos it's going inside,

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you've got the friction constantly of the socket and the joint.

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Coated with PTFE.

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It's inert. That's the other great thing -

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it doesn't react with anything.

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So you can put it in the body and it's going to be fine.

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'I'm chuffed to have discovered that the coating on my frying pan

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'is the world's most slippery plastic,

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'Mark isn't satisfied.

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'He reckons the true Wonderstuff in this story

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'and the key to why it works,

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'is not the non-stick polymer itself,

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'but a remarkable natural ingredient in PTFE.

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'He wants to get to the bottom of it, literally,

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'in this mine in Derbyshire.

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'Here we go.'

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Have I mentioned that I'm claustrophobic?

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It does involve a bit of down. I have to admit that.

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'The Blue John crystal mine goes down 245 steps.'

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We're going right underneath the Pennines, Jane.

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Down, down, down.

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This had so better be worth it.

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It's like Raiders Of The Lost Ark down here.

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Or Raiders Of The Lost Mark, hopefully, in a minute!

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'But what on earth is all the way down here

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'that could be my Wonderstuff?'

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I've brought you here to see a very special piece of rock.

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It's all around us. This is a mineral fluorspar.

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It has in it this element fluorine

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and we react fluorine with the ingredients of polyethene

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and we get this amazing other plastic,

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which revolutionises your life.

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'I still don't get how the fluorine you extract from these rocks

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'makes PTFE such a super slippery plastic.'

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-I've got some here, actually.

-Oh, it's a gas.

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It's a green gas and it's incredibly reactive.

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It's so reactive we had to put it into two containers,

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and even then, it's trying to get out.

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This stuff will react with almost anything.

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So, you never find it on its own

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because anything it comes across, it just forms a compound with.

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'I'm sure I want something that reactive

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'coming into contact with my food.

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'But Mark tells me that it's this super reactivity

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'and the strength of the attraction between the fluorine

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'and other elements in PTFE

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'that are the secret to its slippery success.'

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The fluorine bonds in the PTFE -

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they are so uninterested in bonding to anything else

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that they make it non-stick.

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All they're doing is handing over the energy, the heat,

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and they're not laying claim to anything else.

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'So it was worth sticking with Mark all along.

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'Scratching the surface of non-stick frying pans

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'revealed the true Wonderstuff to be fluorine gas.

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'Fluorine is a dangerously powerful oxidiser

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'and so reactive it only exists in its pure form out in space.

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'Here on Earth,

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'its ability to react with a wide range of other substances

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'make it extremely useful.

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'Plus, it's gentle enough to be added to toothpaste

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'to keep our tooth enamel strong.

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'So, I've discovered some of the stickiest

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'and the slipperiest substances on the planet,

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'but I'm still stuck on one other question.'

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What's the stuff that every home is literally covered in?

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In fact, it's probably staring you in the face right now.

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'I'm talking about household paint.

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'How can it be runny enough for us to roll on,

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'yet still sticky enough to stay on the wall?

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'So if I'm searching for the Wonderstuff in paint,

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'surely that means a nice trip to the Sistine Chapel?'

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Some reporters get to cover the Oscars,

0:17:500:17:53

others get to go down the Amazon.

0:17:530:17:55

I get to come to a paint factory in Slough.

0:17:550:17:59

'And that's because Slough is home to AkzoNobel,

0:18:010:18:05

'who discovered that famous polymer so crucial in PTFE -

0:18:050:18:09

'polyethene.

0:18:090:18:10

'They also make a lot of paint.

0:18:100:18:12

'Richard Barcock is their UK Paint Technical Manager

0:18:130:18:17

'For Decorative Coatings, no less.'

0:18:170:18:19

So, Richard, in general terms, what is paint exactly?

0:18:190:18:23

Paint is a coloured powder in a liquid glue-like medium,

0:18:230:18:28

which you can easily apply to surfaces in your home.

0:18:280:18:31

'Richard breaks down exactly what's in a basic paint for me.

0:18:340:18:39

'There's water,

0:18:390:18:41

-'something to make it opaque...'

-Which gives you this good covering.

0:18:410:18:45

-'..thickener...'

-To increase viscosity of the paint.

0:18:450:18:49

'..a surfactant and an anti-foaming agent...'

0:18:490:18:52

To keep that level of bubbles down.

0:18:520:18:53

'..and then, there's a binder, which I'm told is basically,

0:18:530:18:57

'yes, you've guessed it - glue.

0:18:570:19:00

'The boffins here test different gluey binders to destruction.

0:19:020:19:06

'They're stretched, scuffed and exposed to the elements

0:19:060:19:09

'to find the binder best suited for any surface

0:19:090:19:13

'you might choose to paint.

0:19:130:19:14

'And they've perfected another clever property in their paint as -

0:19:160:19:19

'watch out, here comes another fancy title -

0:19:190:19:22

'Physical Characterisation Team Leader,

0:19:220:19:24

'Dr Tom Kerwin explains.'

0:19:240:19:27

One of the tests that we do here

0:19:270:19:29

to get a feel for the consistency of the paint

0:19:290:19:31

is actually just try and cut a cube from it.

0:19:310:19:34

You'll see that,

0:19:350:19:37

-we can cut this cube out.

-Look at that!

0:19:370:19:40

A slice of paint.

0:19:400:19:41

'So, in the tub, it's solid,

0:19:410:19:44

'but stir it up and it goes all liquidy.'

0:19:440:19:47

Can I have a go? I like a bit of mixing.

0:19:470:19:50

Yeah, have a go.

0:19:500:19:51

Give it a mix and then have a go at cutting another cube.

0:19:510:19:54

Look at that. Trying to cut a cube out of the paint.

0:19:540:19:58

That is fantastic.

0:20:010:20:02

That, now, would go on a wall very nicely indeed.

0:20:020:20:06

'It's now miraculously lost its stickiness

0:20:060:20:08

'and is much easier to apply to the walls.'

0:20:080:20:12

It has this key property known as shear-thinning.

0:20:120:20:14

That means that the viscosity,

0:20:140:20:16

the resistance of the paint to flowing,

0:20:160:20:19

decreases the harder you try and push it.

0:20:190:20:21

And when you stop sort of, applying a force to it,

0:20:210:20:25

does it then solidify again?

0:20:250:20:27

Exactly. That structure we built with the thickeners

0:20:270:20:30

comes back and stops it slipping back off the wall.

0:20:300:20:33

'So the clever paint polymer goes sticky again

0:20:330:20:37

'and dries hard and fast to the wall.'

0:20:370:20:39

-Clever!

-Indeed.

-Yeah, fantastic.

0:20:390:20:42

'Seeing how much science goes into a pot of household paint

0:20:420:20:47

'has made me come over a bit EMULSION-al!

0:20:470:20:50

'But hold on. Even though I now understand how it sticks to my wall,

0:20:510:20:55

'aren't we forgetting the most obvious thing about paint -

0:20:550:20:58

'its colour?'

0:20:580:20:59

For example, Bongo Jazz, anyone?

0:21:010:21:04

It's orange, apparently.

0:21:040:21:05

We buy 300 million litres a year of this stuff.

0:21:050:21:11

'We can now get hold of just about any shade under the sun.

0:21:110:21:15

'So is there any hidden genius I need to know

0:21:170:21:20

'about what gives paint its colour?

0:21:200:21:23

'I've agreed to a rendezvous in a secret location outside Oxford

0:21:230:21:26

'with architectural colour consultant Patrick Baty...'

0:21:260:21:30

A yellow ochre pigment in this country.

0:21:300:21:33

'..and avid pigment expert Keith Edwards.

0:21:330:21:36

'His speciality - digging colours right out of the ground.'

0:21:360:21:40

Hi, Keith.

0:21:400:21:41

To my untrained eye, I'd think that was sand.

0:21:410:21:45

Well, it is partly sand,

0:21:450:21:47

but mostly, it's very pure ochre pigment.

0:21:470:21:50

It was used by famous artists such as Constable, Turner,

0:21:500:21:54

from probably the 17th century up until the early 20th century.

0:21:540:21:59

So special stuff?

0:21:590:22:00

Very special stuff.

0:22:000:22:02

It feels like cumin or something like that.

0:22:020:22:05

It is very like it, yes.

0:22:050:22:07

'Apparently, natural paint pigments like this

0:22:090:22:12

'have been used for over 30,000 years.

0:22:120:22:16

'Keith's spent most of his lifetime in pursuit of perfection.'

0:22:160:22:20

We've got some lovely colours. What's this purple one?

0:22:200:22:23

It's murex purple - it's the most expensive pigment ever produced.

0:22:230:22:28

-Its present value is about £50,000 a single ounce.

-Goodness me!

0:22:280:22:34

-So where does it come from?

-It comes from the murex shellfish -

0:22:340:22:37

a sea snail from the Mediterranean.

0:22:370:22:40

'Keith's commitment to colours is astonishing.'

0:22:400:22:42

Keith, can I just ask you, what colour is your living room?

0:22:420:22:46

That's a hard one.

0:22:460:22:48

-Don't say magnolia!

-Yes, actually, it is.

0:22:480:22:52

'But in my hunt for what gives paint its colour,

0:22:520:22:55

'he's got a bit of a shocking revelation.'

0:22:550:22:57

These, really, are only stains.

0:22:570:23:00

That's the basis of modern paint.

0:23:000:23:03

We can't do without titanium dioxide.

0:23:030:23:05

It's the purest white we have, really.

0:23:050:23:07

Yes. It is the purest, most opaque white we have.

0:23:070:23:10

Paint without titanium dioxide

0:23:100:23:12

would be like making a sandwich without bread.

0:23:120:23:15

'But why is this white pigment so special?

0:23:150:23:18

'Apparently, it's because titanium dioxide

0:23:180:23:21

'makes such a dense and bright colour.

0:23:210:23:23

'Back in London at Patrick's shop, I learn that titanium dioxide

0:23:240:23:28

'is now in pretty much every pot of paint we buy,

0:23:280:23:30

'whatever the colour.

0:23:300:23:32

'And Patrick owns a unique piece of history -

0:23:360:23:39

'a tiny chip of paint that shows why titanium white became so invaluable.'

0:23:390:23:44

What we've got here are 71 individual schemes of paint.

0:23:440:23:49

These were applied to the outside of a building

0:23:490:23:52

that we know was built in 1705.

0:23:520:23:54

What we've got there is the full history of the house,

0:23:540:23:57

which takes us right the way through

0:23:570:23:59

things like the discovery of Australia.

0:23:590:24:01

History encapsulated in a little chip of paint.

0:24:010:24:05

A little chip of paint.

0:24:050:24:07

'Patrick's had a photograph made so we can see what's happening up close.

0:24:070:24:10

'It turns out the old base for paint was downright dangerous.'

0:24:100:24:15

From 1705 to about 1939, here,

0:24:150:24:20

all of these are based on lead carbonate.

0:24:200:24:23

-That is the main constituent of these paints.

-Poison?

-Indeed.

0:24:230:24:26

-Highly toxic.

-Good grief!

0:24:260:24:28

So, we've got lead carbonate through to the Second World War.

0:24:280:24:31

We then have a couple of schemes based on zinc oxide.

0:24:310:24:34

We've got the introduction of brilliant white.

0:24:340:24:37

You can see this much brighter sequence of coats,

0:24:370:24:40

which is about 1960, 1962.

0:24:400:24:43

-So, that's when they started to use the words brilliant white...

-Absolutely.

0:24:430:24:47

It was quite impossible to achieve a colour like that,

0:24:470:24:50

a bright white, in these earlier days.

0:24:500:24:52

'And all that's down to good old titanium dioxide.'

0:24:520:24:56

It's non-toxic. It's readily available. It's not too expensive.

0:24:560:25:01

Most importantly for a paint, it covers very well indeed.

0:25:010:25:03

A couple of coats, that's all you need.

0:25:030:25:06

-So, it revolutionised the paint industry?

-Completely.

0:25:060:25:09

'With cheap, safe titanium dioxide in your paint,

0:25:090:25:13

'all you need is a couple of coats to get good coverage

0:25:130:25:16

'and rich colour.

0:25:160:25:18

'But exactly how is this extraordinary ingredient

0:25:180:25:21

'achieving this? Back to Mark.'

0:25:210:25:23

I've got a sample of wallpaper,

0:25:230:25:25

which you may or may not want to get rid of.

0:25:250:25:28

It's all the rage now again, you know, florals.

0:25:280:25:30

-We'll have an argument about this.

-I don't think I'd have it on my wall.

0:25:300:25:33

We want to get rid of it with some white paint.

0:25:330:25:36

'Time for the ultimate paint challenge.

0:25:370:25:40

'Mark has mixed up some titanium dioxide and plain water

0:25:400:25:44

'to see how well it covers up the horrors of his floral wallpaper.

0:25:440:25:49

'After just one coat, the results are striking.'

0:25:490:25:53

These titanium particles are little crystals.

0:25:530:25:55

The light's coming in,

0:25:550:25:57

and it's only getting through a small part of the crystal

0:25:570:26:00

before it gets pinged out again

0:26:000:26:02

because it's got a very high refractive index.

0:26:020:26:05

'That means it's like thousands of tiny mirrors

0:26:050:26:08

'bouncing the light back out, and that's not all.'

0:26:080:26:11

It does some other weird things, too. It makes surfaces self-clean.

0:26:110:26:15

It's photocatalytic. So, when light hits it,

0:26:150:26:17

if there's any organic matter near it,

0:26:170:26:20

it makes it disintegrate.

0:26:200:26:22

That sound astonishingly clever.

0:26:220:26:24

'When sunlight hits a titanium dioxide coating,

0:26:240:26:28

'any dirt rapidly oxidises and can then be washed off by the rain.'

0:26:280:26:32

-TD, let's hear it for TD.

-I totally agree with you.

0:26:320:26:36

We use four million tonnes

0:26:370:26:40

of this naturally occurring mineral every year

0:26:400:26:43

as a base for paint of any colour.

0:26:430:26:45

Its ability to give excellent coverage

0:26:450:26:47

means it also turns up in cosmetics and sun creams.

0:26:470:26:51

Pretty much everything that's white in your house

0:26:510:26:54

contains titanium dioxide.

0:26:540:26:56

Your white goods, your writing paper.

0:26:560:26:59

It's even in your food as E number 171.

0:26:590:27:03

Cottage cheese with added microscopic mirrors, anyone?

0:27:030:27:06

For me, the search for the Wonderstuff

0:27:090:27:11

behind why things stick or don't stick

0:27:110:27:13

has really brought it home how we rely on clever chemistry

0:27:130:27:16

every single day without even realising it.

0:27:160:27:19

The chance discovery of the world's most reactive element, fluorine,

0:27:190:27:23

led to the chance discovery

0:27:230:27:25

of one of the world's most slippery substances, PTFE

0:27:250:27:29

which in turn, led to the culinary revolution,

0:27:290:27:32

enabled by the non-stick pan.

0:27:320:27:35

So who would've thought there was such a fascinating history

0:27:350:27:39

behind an everyday object we all take for granted?

0:27:390:27:42

'Next time, I get under the skin of preening products...'

0:27:420:27:46

Ow!

0:27:460:27:47

'..in my search for the magical mist-grabber in moisturiser.'

0:27:470:27:52

I'm absolutely amazed that just a clear liquid

0:27:520:27:55

can do this amazing thing.

0:27:550:27:57

'Mark tries to explain how anti-perspirant

0:27:570:28:00

'prevents pungent pongs.'

0:28:000:28:02

What if too much comes out? Then you feel uncomfortable.

0:28:020:28:05

I wouldn't like to meet a man who sweated quite that much.

0:28:050:28:08

'And on the hunt for the Wonderstuff in sunscreen,

0:28:080:28:11

'I stoically endure utter humiliation,

0:28:110:28:14

'all in the name of science.'

0:28:140:28:15

Oh! Oh! Oh, God!

0:28:150:28:19

Subtitles by Red Bee Media Ltd

0:28:350:28:38

E-mail [email protected]

0:28:380:28:41

Jane Moore busts open the stuff we rely on when it comes to waging domestic germ warfare.

Jane's investigates the stickiness of household essentials. She discovers the wonderstuff in super-strength glues, how paint manages to stick to the wall and, on the flip side, what's on non-stick frying pans that makes it the world's slipperiest substance.