ABSTRACT
The initiation by metals and metal-containing compounds generally takes place as a redox process [1]. In this type of initiation, free radicals responsible for polymerization are generated as transient intermediates in the course of a redox reaction. Essentially, this involves an electron transfer process followed by scission to give normally one free radical. The oxidant is generally referred to as the initiator or the catalyst, and the reducing agent is called the activator or the accelerator. Notably, depending on its oxidation state, the metal can act as reducing or oxidizing agent.
