New materials

Question 1

What are the two groups of new materials?

Answer 1

• Smart materials.

- Nanoparticles.

Question 2

How do smart materials behave?

Answer 2

Very differently depending on the conditions (e.g. temperature).

Question 3

What is an example of a smart material?

Answer 3

Nitinol.

Question 4

What nitinol’s nickname?

Answer 4

A shape memory alloy.

Question 5

What is nitinol?

Answer 5

A metal alloy (about half nickel, half titanium).

Question 6

What can you do to nitinol?

Answer 6

When it’s cool you can bend it and twist it like rubber.

Question 7

What happens when nitinol is bent too far?

Answer 7

It stays bent.

Question 8

What can you do after you’ve bent nitinol to far that it stays bent?

Answer 8

You can heat it above a certain temperature, and it goes back to a remembered shape.

Question 9

What is nitinol used in?

Answer 9

• Glasses frames.

- Dental braces.

Question 10

Why is nitinol used in glasses frames?

Answer 10

Because if you accidentally bend them, you can just heat them above a certain temperature (put them in a bowl of hot water) and they return to their shape.

Question 11

Why is nitinol used in dental braces?

Answer 11

As in the mouth it warms and tries to return to a remembered shape, and so it gently pulls the teeth with it.

Question 12

What are nanoparticles?

Answer 12

Really tiny particles, 1-100 manometres across.

Question 13

What is one nanometre?

Answer 13

0.000000001 m.

Question 14

What do nanoparticles contain?

Answer 14

A few hundred atoms.

Question 15

What do nanoparticles include?

Answer 15

Fullerenes.

Question 16

What are fullerenes?

Answer 16

Molecules of carbon.

Question 17

What are fullerenes shaped like?

Answer 17

Hollow balls or closed tubes.

Question 18

How are the carbon atoms in fullerenes arranged?

Answer 18

In hexagonal rings.

Question 19

What do different fullerenes contain?

Answer 19

Different numbers of carbon atoms.

Question 20

What does a nanoparticles have in comparison to the chemical it is made from?

Answer 20

Very different properties (e.g. fullerenes have different properties from the big lumps of carbon).

Question 21

What can we do to fullerenes?

Answer 21

Join them together to form nanotubes.

Question 22

What are fullerene nanotubes?

Answer 22

Tiny hollow carbon tubes, a few nanometres across.

Question 23

What can fullerene nanotubes be used to do?

Answer 23

Reinforce graphite in tennis rackets.

Question 24

Why are fullerene nanotubes used to reinforce graphite in tennis rackets?

Answer 24

As all the covalent bonds make carbon nanotubes very strong.

Question 25

What is using nanoparticles known as?

Answer 25

Nanoscience.

Question 26

What is happening in science regarding nanoparticles?

Answer 26

Many new uses of nanoparticles are being developed.

Question 27

What new uses of nanoparticles are being developed in science?

Answer 27

- To make new industrial catalysts. - To make sensors that detect one type of molecule only (highly specific sensors). - To make stronger, lighter building materials. - To make new cosmetics. - In nanomedicine. - To make new lubricant coatings. - In tiny electric circuits for computer chips.

Question 28

Why can nanoparticles be used to make new industrial catalysts?

Answer 28

As they have a huge surface area to volume ratio.

Question 29

What are the highly specific sensors made by nanoparticles being used to test?

Answer 29

For water purity.

Question 30

Why are nanoparticles used to make new cosmetics?

Answer 30

(E.g. sun tan cream and deodorant), because the small particles do their job but don't leave white marks on the skin.

Question 31

How can nanoparticles be used in medicine (nanomedicine)?

Answer 31

The idea is that tiny fullerenes are absorbed more easily by the body than most particles, so they could deliver drugs to the right cells where they are needed.

Question 32

What are new lubricant coatings being developed for using nanoparticles?

Answer 32

They are being developed with fullerenes, to reduce friction (a bit like ball bearings) and could be used in places like artificial joints and gears.

Question 33

Why are nanoparticles being used in tiny electric circuits?

Answer 33

As nanotubes conduct electricity.