Condensation Polymerization:Kevlar :: Addition Polymerization:?

Condensation polymerization joins monomers with the loss of a small molecule, like water or HCl, to make Kevlar from terephthaloyl chloride and p‑phenylenediamine. Addition polymerization joins monomers by adding the entire monomer unit, without losing a small molecule. The most common polymer made by this process is polyethylene, formed by adding ethylene units together. For example, when ethylene gas is polymerized, each CH₂=CH₂ unit adds to the growing chain, producing long chains of –CH₂–CH₂– repeated many times. This gives a lightweight, flexible plastic used in everything from plastic bags to fishing lines.