AQA Chem4: Polymers

Properties:

• chemically inert
• not attacked by acids, bases or oxidising agents
• non-biodegradable

Disposal:

• Incineration - leads to production of toxic and greenhouse gases, e.g. polurathanes burn giving  NO2 and HCN
• Recycling - expensive but the best alternative

• they are formed from two monomers each with functional groups at both ends of the molecule, when they react a small molecule (usually water) is eliminated
• there are two types of condensation polymer - polyester and polyamide
• condensation polymers are biodegradable as you can hydrolyse them

Polyesters:

• formed by the reaction of a dicarboxylic acid and a diol in which an ester link is formed
• generally - HOOC-(CH2)x-COOH + HO-(CH2)y --> -[CO(CH2)x-COO(CH2)y-O]- + 2H2O
• an example is terylene which is formed from benzene-1,4-dioc acid and ethan-1,2-diol

Polyamide:

• formed between the reaction of a dicarboxylic acid and a diamine and a peptide link is formed
• generally - HOOC-(CH2)x + H2N-(CH2)y-NH2 --> -[CO(CH2)x-CO-NH-(CH2)y-NH]- + H2O
• an example is nylon which is made from hexandioc acid and 1,6-diaminohexane