IGCSE Coordinated Chemistry Lesson 5 Polymers.pptx

IGCSE Coordinated Chemistry Lesson 5 Polymers.pptx

1. P olymer s Do now : If two molecules (e.g. ethene) are to join together, what would need to happen? Why? See if you can draw a molecule made of 2 ethene’s joined together.

2. What do I need to know?

3. Definitions Monomer - Monomers are small molecules that can join up to make a very large molecule called a polymer. Polymer - Polymers are large molecules that are made up of many repeated small molecules. Polymerisation - The process of monomers (small molecules) joining up to form a polymer (long molecule) is called polymerisation. Poly - means many -mer means part/segment Mono means one

4. Monomers make Polymers ETHENE is a MONOMER . Step 1: Break the double bond Step 2: Add the monomers together: This makes a POLYMER called POLYETH ENE

5. Many MONO mers make a POLY mer!

6. Monomers: Single units Polymer: Many monomers joined together Catalyst Polymers are made by adding monomers together, often using a catalyst. Making polymers

7. Monomers: Polymer: Catalyst Different monomers make different polymers (plastics) which have different properties and uses. Making polymers Polymer properties are dictated by the monomers that make it.

8. To make things simple, we usually only draw one unit of t his repeating structure . It should have: at least two carbon atoms, extended bonds, brackets and an n number. Repeating unit

9. Drawing polymers When given a monomer, the double bond needs to break to make the polymer. General formula for addition polymerisation:

10. Condensation polymerisation

11. Nylon - condensation polymer (polyamide)

12. Nylon - polyamide It is made from monomers containing acid and amine groups. Amide functional group

13. Natural polyamides Amino acids (that form proteins) can form polyamides. So proteins are natural polyamides.

14. Nylon Nylon is a poly amide formed from monomers. Amide linkage Amide linkage

15. Addition vs condensation polymers Addition polymers are made from monomers containing double bonds. Addition polymers are saturated, so are very unreactive. This means they cannot be broken down easily (they can take hundreds of years). The monomer ethene makes the polymer polyethene. Condensation polymers can be broken down (so they are biodegradable). Polyamides are condensation polymers. Different types of polymers have different linkages.

16. Complete the worksheet

17. Mark your work

18. Mark your work

19. Plenary Quiz What is the word we use for single units? MONOMERS

20. Plenary Quiz What is the word we use for many units joined together? POLYMERS

21. Plenary Quiz What does ‘poly’ mean? MANY

22. Plenary Quiz What does ‘mer’ mean? PARTS OR SEGMENTS

23. Plenary Quiz Name a molecule that is not a monomer. E.g. water

24. Plenary Quiz Name a monomer E.g. Ethene