'Living' and controlled radical polymerization

Radical polymerizations cannot truly be ‘living’ because of the inevitable termination between growing radicals. However, relatively good control of molecular weights, polydispersities and terminal functionalities can be achieved by using either unimolecular or bimolecular exchange between growing radicals and dormant chains. The dormant chains can be in the form of either covalent species or organometallic compounds. Some systems based on alkoxyamines, organochromium compounds, organoaluminum compounds and alkyl iodides were studied and are discussed in detail.