Polymer Disposal (Edexcel International A Level Chemistry): Revision Note

Polymer Disposal

• Chemists have designed ways to remove toxic waste products like HCl before they are emitted into the atmosphere

• The waste gases from the incinerator are scrubbed/reacted with a base or carbonate

• The base reacts with the acidic HCl gas, neutralising it

  • eg. CaO (s) + 2HCl (aq)→CaCl₂ (aq) + H₂O (l) 

• Chemists have also developed biodegradable and compostable polymers

Biodegradable polymers

• Biodegradable polymers can be broken down over time by microorganisms

  • Common products from this process include carbon dioxide, water and other organic compounds

• The polyester and polyamide condensation polymers are considered to be biodegradable as they can be broken down using hydrolysis reactions

  • This is a major advantage over the polymers produced using alkene monomers (polyalkenes)

  • When polyesters and polyamides are taken to landfill sites, they can be broken down easily and their products used for other applications

Compostable polymers

• Compostable polymers are commonly plant-based

  • Plant starch is being used in the production of biodegradable bin liners

  • Sugar cane fibres are replacing polystyrene in the production of disposable plates and cups

• Compostable polymers degrade naturally leaving no harmful residues