Poly(tetrafluoroethene) (PTFE) is produced via addition polymerisation, whereas polyethylene terephthalate (PET) is a polyester produced via condensation polymerisation.
Contrast the molecular structures of the monomers used to synthesise addition polymers, such as PTFE, with those used to synthesise condensation polymers, such as PET.
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Practise Edexcel GCSE Chemistry Polymers with exam-style questions for Foundation and Higher tier. 100 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.