‘Immortal’ polymerization. Polymerization of epoxide catalysed by an aluminium porphyrin–alcohol system

Abstract
Ring-opening polymerization of epoxide catalysed by a (tetraphenylporphinato)aluminium chloride-alcohol system affords a polyether having a controlled molecular weight of narrow distribution with the number of the polymer molecules exceeding the number of aluminium porphyrin molecules; this is due to exchange between the alcohol and the (porphinato)aluminium alkoxide, which is the active species, resulting in the ‘immortal’ nature of the polymerization.