Login-Verarbeitung ...

Trial ends in Request Full Access Tell Your Colleague About Jove

21.14: Anionic Chain-Growth Polymerization: Mechanism

JoVE Core
Organic Chemistry

Ein Abonnement für JoVE ist erforderlich, um diesen Inhalt ansehen zu können. Melden Sie sich an oder starten Sie Ihre kostenlose Testversion.

Anionic Chain-Growth Polymerization: Mechanism

21.14: Anionic Chain-Growth Polymerization: Mechanism

The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael acceptor. Consequently, a dimer is formed that acts as a new carbanion. The propagation step repeats itself, thereby enabling the polymer chain to extend. The polymer chain continues to grow until a weak acid or an electrophile is added to terminate the polymerization process. Interestingly, in the absence of any terminating agents, the propagating chain’s end acts as a stabilized carbanion site, and the polymerization process continues uniformly as long as the monomers are available. Therefore, anionic polymers are often referred to as living polymers.


Keywords: Anionic Chain-growth Polymerization Initiation Propagation Termination Nucleophilic Anion Carbanion Michael Donor Michael Acceptor Living Polymers

Get cutting-edge science videos from JoVE sent straight to your inbox every month.

Waiting X
Simple Hit Counter