The iniferter technique in radical polymerization under UV and thermal conditions: a comparative study

UV and thermal polymerisations of styrene were carried out in the presence of conventional 'iniferters'. The mechanisms of the two methods were investigated and provided new insight into the livingness of the so-called iniferter technique. Chain extension polymerisations were performed using symmetrical iniferters to check the living character of this technique under UV and thermal polymerization conditions. In accordance with the work of Otsu, we have shown that polymerisation under UV irradiation initiated by iniferters proceeds via the classical iniferter living (controlled) mechanism. On the other hand, thermal polymerisations were predominantly controlled by the reversible addition-fragmentation chain transfer (RAFT) mechanism.