Concept:Addition (chain-growth) polymers are formed by the successive addition of unsaturated monomer units across double or triple bonds without the elimination of any small by-product molecules.
Formula / Reaction:$$n\,\text{CH}_2=\text{CH}-\text{Cl} \xrightarrow{\text{Initiator}} -[\text{CH}_2-\text{CH}(\text{Cl})]_n-$$
Solution:- Polyvinyl chloride (PVC) is produced by the free-radical addition polymerization of vinyl chloride (chloroethene).
- The empirical formula of the polymer repeating unit is identical to that of the monomer, confirming addition polymerization.
Why other options are incorrect:- nylon 6,6: A condensation polyamide synthesized from hexamethylenediamine and adipic acid with elimination of \(\text{H}_2\text{O}\).
- nylon 6,10: A condensation polyamide formed from hexamethylenediamine and sebacoyl chloride/sebacic acid.
- polyester: A condensation polymer formed between diols and dicarboxylic acids with elimination of \(\text{H}_2\text{O}\).
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