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Polymers

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  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:

  6. Polyethylene

  7. Polypropene • Made from propene monomers

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

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

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

  11. Polystyrene

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

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

  14. 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

  15. 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

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

  17. Polyesters • Formed between dicarboxylic acid and diol

  18. Polyesters • Formed between dicarboxylic acid and diol

  19. Polyamides • Formed between dicarboxylic acid and diamine

  20. Polyamides • Formed between dicarboxylic acid and diamine