Polymers

1. Polymers

2. What Are Polymers? • Large molecule that consists of lots of small repeating subunits • Subunits are called monomers • Polymers are formed when monomers are linked together is a process called polymerization

3. Addition Polymers • Polymers are linked through addition reactions • Three stages in synthesis • Initiation • Propagation • Termination

4. Polyethylene • Polymer made from ethene monomers

5. Polyethylene • Polymer made from ethene monomers • Short form notation:

7. Polyethylene

8. Polypropene • Made from propene monomers

9. Polypropene • Made from propene monomers • Used in rope and carpets • Short form notation:

10. Polyvinyl Chloride (PVC) • Made with chloroethene (vinyl chloride) monomers

11. Polyvinyl Chloride (PVC) • Made with chloroethene (vinyl chloride) monomers • Used in electrical wire insulation, plastic piping, coating on fabrics • Short form notation:

12. Polystyrene

13. Polystyrene • Made from (styrene) phenylethene • Very commonly used

14. Substituted Groups • Change the properties of polymer • Teflon monomer: tetrafluroethane • Plexiglass monomer: methyl propenoate

16. Crosslinking • Occurs when links can be formed in 2 directions • Diene monomers can form bridges between chains • Diene doesn’t have to be main monomer • Increases polymers’ strength

17. Plastic Properties • Substituted ethene (vinyl) monomers considered “plastics” • Saturated alkanes • Very stable • Unreactive • Flexible and mouldable solids or liquids • Weak van der Waals forces • Softened by heating • Disrupts forces

19. Condensation Polymers • Monomer units are joined by condensation reactions • Monomer units must have functional groups at each end

20. Polyesters • Formed between dicarboxylic acid and diol

21. Polyesters • Formed between dicarboxylic acid and diol

22. Polyamides • Formed between dicarboxylic acid and diamine

23. Polyamides • Formed between dicarboxylic acid and diamine