Polymers

• What are the two types of polymerisation?

  Addition and condensation
• What forms an addition polymer?

  Unsaturated monomers react to form a polymer
• What type of bonds do monomers in addition polymerisation contain?

  C=C bonds
• Why are poly(alkenes) chemically inert?

  Due to strong C-C and C-H bonds
• What is the nature of poly(alkenes) that makes them non-biodegradable?

  Non-polar nature of the bonds
• How do you draw the polymer repeating unit for an alkene?

  Draw the monomer with groups around the double bond
• What is produced as a side-product in condensation polymerisation?

  A small molecule like H2O or HCl
• What are the two most common types of condensation polymers?

  Polyesters and polyamides
• What type of linkages do polyesters and polyamides form?

  Ester linkage and amide linkage
• What functional groups do the monomers in condensation polymerisation usually have?

  Same functional group on both ends
• What is the reaction of carboxylic acid and alcohol in condensation polymerisation?

  Carboxylic Acid + Alcohol → Ester + water
• What is the reaction of acyl chloride and alcohol in condensation polymerisation?

  Acyl chloride + Alcohol → Ester + HCl
• What is the reaction of carboxylic acid and amine in condensation polymerisation?

  Carboxylic Acid + Amine → Amide + water
• What is the reaction of acyl chloride and amine in condensation polymerisation?

  Acyl chloride + Amine → Amide + HCl
• What are the reactions used to form polyesters and polyamides?

  • dicarboxylic acid + diol → poly(ester) + water
  • diacyl dichloride + diol → poly(ester) + HCl
  • dicarboxylic acid + diamine → poly(amide) + water
  • diacyl dichloride + diamine → poly(amide) + HCl
• What is Terylene?

  A common polyester used in fabrics
• What is the significance of the -1 in the Terylene formation equation?

  It accounts for H and OH at chain ends
• What is Nylon 6,6 made from?

  Hexanedioic acid and hexane-1,6-diamine
• What does the 6,6 in Nylon 6,6 represent?

  6 carbons in each of the monomers
• How can polyamides and polyesters form from one monomer?

  • One monomer contains both functional groups needed to react
  • Can undergo self-condensation to form polymers
• What is Kevlar?

  A common polyamide known for strength
• What can some compounds form under different conditions?

  Various cyclic esters
• What is the most common method of polymer waste disposal in the UK?

  Landfill
• What is a consequence of European regulations on landfill usage?

  Councils will be charged more for landfill
• Why do polyalkenes take many years to break down?

  They are non-biodegradable
• What is the benefit of using biodegradable plastics?

  Improves rates of decomposition
• What happens during incineration of rubbish?

  Rubbish is burnt to generate electricity
• What is a drawback of incineration?

  Some toxins can be released
• What is the advantage of recycling polymers?

  Saves raw materials from crude oil
• What is a challenge in recycling polymers?

  Polymers need collecting and sorting
• What can thermoplastic polymers do during recycling?

  They can be melted down and reshaped
• How can polyesters and polyamides be broken down?

  By hydrolysis
• What do polyesters and polyamides yield upon hydrolysis?

  The original monomers
• What type of bonding exists in polyesters?

  Permanently dipole forces and van der Waals forces
• What type of bonding exists in polyamides?

  Hydrogen bonding and van der Waals forces
• Why do polyamides have higher melting points than polyesters?

  Due to hydrogen bonding in polyamides
• What explains the reactivity of condensation polymers?

  The presence of polar bonds attracting nucleophiles
• What type of link does the polymer with both an amide and ester link have?

  Both amide and ester link
• What happens to the original monomers during hydrolysis of polyesters and polyamides?

  They form in salt form depending on conditions
• What is the role of NaOH in the hydrolysis reaction?

  It acts as a base