HIGH-SPEED IMMORTAL POLYMERIZATION OF EPOXIDES INITIATED WITH ALUMINUM PORPHYRIN - ACCELERATION OF PROPAGATION AND CHAIN-TRANSFER REACTIONSBY A LEWIS-ACID

Immortal polymerization of epoxides with (5,10,15,20-tetraphenylporphi nato)aluminum chloride ((TPP)AlCl, 1a) as the initiator coupled with a lcohol or phenol as the protic chain-transfer agent (ROH) was dramatic ally accelerated by a sterically crowded organoaluminum compound such as methylaluminum bis-(2,6-di-tert-butyl-4-methylphenolate) (2a), affo rding polymers of controlled molecular weights with narrow distributio n. The number of the polymer molecules (N(p)) is equal to the sum of t he numbers of molecules of 1a (N(TPP)) and ROH (N(ROH)). By taking adv antage of this acceleration method, the turnover number (N(p)/N(TPP)) of the immortal polymerization was increased up to 1000 under selected conditions.