Select which is not included in the chain polymerization mechanism.a.Polyesterb.Vinylc.Allyld.Dienes

The chain polymerization mechanism includes the formation of polymers by adding monomer units in a chain-like fashion. This process involves three main steps: initiation, propagation, and termination.

a. Polyester: Polyester is a type of polymer that is formed through a different process known as condensation polymerization or step-growth polymerization, not chain polymerization.

b. Vinyl: Vinyl polymers are a type of polymer that are formed through chain polymerization.

c. Allyl: Allyl compounds can also undergo chain polymerization.

d. Dienes: Dienes, compounds with two double bonds, can also participate in chain polymerization.

So, the one that is not included in the chain polymerization mechanism is Polyester.