NANOTECHNOLOGY

1. NANOTECHNOLOGY What is a nanometre?

2. SOME ANT-SWERS - • A nanometre = 10-9 m • An average ant is 5 mm long (5 X 10-3 m) • = 5 million nanometres • An atom is about a tenth of a nanometre in diameter. • Nanotech objects are normally 1 – 100 nm in size. • They are • MACROMOLECULES • World record = 34.7 m length (Lungfish DNA) • And 0.2nm thin • These fold up & so are very little. 2

3. MACROMOLECULES • Macromolecules form the basis for all necessities of our material life; • Food • Shelter • Currency • Communication • Transportation • Health • Clothing 3 • Footnote

4. MACROMOLECULES • Macromolecules have given us • Rubber duckies • Money • Credit cards • Bulletproof vests • Bread • Paper • Clay tablets • Car tyres • Super glue • Chewing gum • 4

5. MACROMOLECULES Macromolecules have given us Rubber duckies Money Credit cards Bulletproof vests Bread Paper Clay tablets Car tyres Super glue Chewing gum AndLIFE!

6. Original definition: Nanotechnology is the building of machines on the scale of molecules. Nano dwarf (Gk) More mod definition: Nanotechnology is the technology of making things that are from a few nanometres to a few hundred nanometres in size. Plastics Fibres Adhesives Elastomers All of these are made of MACROMOLECULES. SO WHAT IS NANOTECHNOLOGY?

7. NANOMACHINES • This is one of the largest nanomachines made. It is made of 15,342 atoms and is a parallel shaft speed - reducer gear.

8. What are polymers?

9. What is a polymer (mer-mer-mer-mer)?Polymers are large molecules – macromolecules – made by the repetitive linking of smaller molecules called monomers.

10. Paper money Plastic money THEY ARE BOTH MADE UP OF POLYMERS MACROMOLECULES AND MONEY 10

11. These notes last longer, don’t get as dirty, can survive the washing machine, are much more difficult to counterfeit and can be recycled. The fine surface means a more detailed design is possible. Australia manufactures currency for more than 26 countries. 11 MACROMOLECULES AND MONEY

14. This was the momentwhen the engines of lifeappeared. This changed the whole planet from a chemical rock into a living, breathing globe. DNA, RNA and proteins are MACROMOLECULES and proteins are dynamic molecular machines. 14 THE BIOINDUSTRIAL REVOLUTION

16. AND WHAT ARE MACROMOLECULES MADE FROM? • Answer: Little carbon compounds. 16 • “Can you do ADDITION,” the White Queen asked. “What’s one and one and one and one and one and one and one and one and one and one?” • Lewis Carroll. Through the Looking Glass • CH2 = CH2 • -CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2- • Polythene is an addition polymer. • CH2=CH-Cl • -CH2-CH-CH2-CH-CH2-CH-CH2-CH-CH2-CH-CH2-CH-CH2-CH-CH2-CH-CH2-CH- • l l l l l l l l l • Cl Cl Cl Cl Cl Cl Cl Cl Cl

17. MACROMOLECULES ARE POLYMERS • Making a macromolecule is called POLYMERISATION. • A POLYMER IS A BIG MOLECULE MADE FROM MANY LITTLE MOLECULES, (at least 100) JOINED BY COVALENT BONDS. They are lined up like pearls on a string. A little molecule used to make a polymeris called a MONOMER. mer-mer-mer-mer-mer-mer-mer-mer-mer-mer-mer-mer- • CH2-CH-CH2-CH-CH2-CH-CH2-CH-CH2-CH-CH2-CH-CH2-CH-CH2-CH-CH2-CH- • l l l l l l l l l CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 • Can you work out the name and structure of the monomer used to make this polymer? 17

18. THERMOPLASTIC POLYMERSTHESE CAN BE RESHAPED. • The strong covalent bonds joining atoms in a polymer are like links in a bicycle chain. Polymer molecules become twisted and tangled like cooked spaghetti. • Thermo – warmth • Plastic – able to be shaped. • A change of shape is a physical change. • Thermoplastics soften on heating & take up the shape of their container. They retain this new shape on cooling but can be reshaped on reheating. • There are no primary bonds between chains. • Polythene • PVC • Polypropylene • Polystyrene • are all thermoplastics and are all made by addition polymerisation. These make up 86% of plastic production. • 18 worms

19. THERMOSETTINGPOLYMERSTHESE CANNOT BE RESHAPED ON HEATING. • Thermosetting polymers do not get softer when heated, they get HARDER. • This is because new primary bonds form between chains making the overall structure more rigid. • The primary bonds between chains are called • cross-links. 19 • Sometimes a second chemical is added as a cross-linker, or the original polymer may have functional groups activated by heating to form cross-links. • Thermosets never become softer again. • A hard-boiled egg cannot be converted into a runny, raw egg. • Stronger heating makes thermosetschar. • Tanning of leather and vulcanisation of rubber are cross- linking processes.

20. Note: Cross-links can be secondary but these require less heat energy to break, resulting in a physical change called? • Melting! • Thermoplastics have only secondary bonds between chains.

21. Foamed plastics have low density because they have lots of little holes. - a pore structure. Cork Wood SYNTHETIC FOAMED PLASTICS Foamed polystyrene Polyurethane foams also Bread Cake FOAMED PLASTICS

22. NANOMACHINES • Proteins are polymers. • Proteins turn energy into useful work. • They are the engines of life. • A working protein has a precise coiled shape that enables it to do a specific task in a cell. • Molecular origami! • Proteins are nanomachines. • Nanobots! • STAY TUNED

23. Practical work • Aim • To make a synthetic, 3D, foamed, cross-linked, thermosetting, biodegradable, polymer. • You will need • 2 egg whites (albumen) • 125 g sucrose 2-O-(α – D – glucopyranosyl) – β – D – fructofuranoside) • Method • Beat at top speed for 7 minutes. • Put spoonfuls on cold greased trays into a preheated oven. (120 – 150)oC • Heat for 60 – 90 minutes. • Cool • EAT!

24. Polymerisation, that is, the production of giant molecules from small molecules, has been recognised as one of the greatest discoveries of all time. THE END