Initiator efficiency in thermal initiation

The proportion of radicals which escape the solvent cage to form initiating radicals is termed the initiator efficiency (/) which is formally defined as follows (eq, 1).  

According to cq. 1, the term/should take into aecount all side reactions that lead to loss of initiator or initiator-derived radicals. These include cage reaction of the initiator-derived radicals (3.2.8), primary radical termination (3.2.9) and transfer to initiator (3.2.10). The relative importance of these processes depends on monomer concentration, medium viscosity and many other factors. 1 hus / is not a constant and typically decreases w ith conversion (see 3.3.1.1.3 and 3.3.2.1.3). 

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