Step 1: Polymerization Classification
Polymerization is categorized into two primary types:
1. Chain-growth polymerization: Monomers are successively added to an expanding polymer chain. This process initiates with free radicals, cations, or anions, and polymerization proceeds via the addition of monomers, typically possessing double bonds.
2. Step-growth polymerization: Polymer formation occurs through reactions between small molecules, establishing covalent bonds and producing a polymer. This method is defined by the reaction of bifunctional or multifunctional monomers to yield a polymer.
Step 2: Polymer Identification
The given polymers are classified as follows:
Teflon: Formed via chain-growth polymerization, involving the addition of tetrafluoroethylene monomers with free radicals present.
Bakelite: A product of step-growth polymerization, synthesized from phenol and formaldehyde.
Nylon: An instance of step-growth polymerization, derived from the reaction of a diamine and a dicarboxylic acid.
Terylene: Also a result of step-growth polymerization, produced by reacting terephthalic acid with ethylene glycol.
Conclusion: Considering the polymerization mechanism and polymer type, Teflon is the polymer synthesized via chain-growth polymerization. Thus, the correct identification is:
\[\boxed{\text{Teflon}}\]