Chemistry – Organic chemistry - Polymers | e-Consult

The reaction between an alkene and a chain-transfer agent to produce a polymer is an addition polymerization.

Role of the catalyst: The catalyst (e.g., Ziegler-Natta catalyst or metallic catalyst) facilitates the addition of the monomers to the growing polymer chain. It does this by coordinating with the monomer and alkene, lowering the activation energy of the reaction and allowing for faster polymerization.

Role of the chain-transfer agent: The chain-transfer agent is a molecule that can terminate the growing polymer chain and initiate a new one. It does this by abstracting a hydrogen atom from the growing polymer chain, effectively stopping the chain growth and creating a new radical that can start a new polymer chain. This helps to control the molecular weight of the polymer.

Example: Polyethylene (PE) is a common example of a polymer produced using this type of reaction. Ethylene (C2H4) monomers add together to form polyethylene chains, with a chain-transfer agent often used to control the polymer's properties.