Polymerisation

• What are the two types of polymerisation?

  Addition and condensation
• What is addition polymerisation?

  • Forms when unsaturated monomers react
  • Monomers contain C=C bonds
  • Chain forms by repeating the same basic unit
• What type of polymers are poly(alkenes)?

  They are chemically inert and non-biodegradable
• Why are poly(alkenes) non-biodegradable?

  Due to the strong C-C and C-H bonds and non-polar nature
• How can you draw the polymer repeating unit for any alkene?

  By first drawing out the monomer with groups of atoms around the double bond
• What is condensation polymerisation?

  • Involves two different monomers
  • A small molecule is released as a side-product (e.g., H2O or HCl)
  • Common types include polyesters and polyamides
• What are the two common types of condensation polymers?

  Polyesters and polyamides
• What functional groups do the monomers in condensation polymerisation usually have?

  They usually have the same functional group on both ends
• What is the reaction for forming an ester from a carboxylic acid and an alcohol?

  Carboxylic Acid + Alcohol → Ester + Water
• What is the reaction for forming an amide from a carboxylic acid and an amine?

  Carboxylic Acid + Amine → Amide + Water
• What reactions are 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 clothing and tire cords
• What is the significance of the -1 in the Terylene formation equation?

  It accounts for the H and OH still present at each end of the chain
• What is Nylon 6,6 made from?

  Hexanedioic acid and Hexane-1,6-diamine
• How can polyamides and polyesters form from one monomer?

  • If the monomer contains both functional groups needed to react
  • Can lead to the formation of cyclic esters under different conditions
• What is the common polyamide known as Kevlar made from?

  1. hydroxypentanoic acid and 4-hydroxybutanoyl chloride
• What are the common methods of polymer disposal?

  • Landfill
  • Incineration
  • Recycling
• What is the most common method of waste disposal in the UK?

  Landfill
• What is a disadvantage of using landfill for polymer disposal?

  Many landfills are reaching capacity
• What is a disadvantage of incineration?

  Some toxins can be released during the process
• What is a benefit of recycling polymers?

  It saves raw materials and precious resources
• What is the chemical reactivity of condensation polymers?

  • Polyesters and polyamides can be broken down by hydrolysis
  • They are biodegradable
• How can polyesters and polyamides be hydrolysed?

  By acid and alkali
• What types of intermolecular bonding exist in condensation polymers?

  • Polyesters: Permanent dipole forces and van der Waals forces
  • 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 that attract nucleophiles and acids
• What type of link does the polymer with both an amide and ester link have?

  It has both an amide and ester link
• What happens during hydrolysis of polyesters and polyamides?

  Original monomers are formed, with carboxylic acid or amine in salt form