Living and Monomer-Selective Copolymerization of n-Butyl Acrylate and Methyl Methacrylate with the Aid of Bis(2,6-di-tert-butylphenoxy)ethylaluminum

Abstract

Anionic polymerizations of n-butyl acrylate (n-BuA) and methyl methacrylate (MMA) in toluene with a combination of tert-butyllithium (t-BuLi) and bis(2,6-di-tert-butylphenoxy)ethylaluminum [EtAl(ODBP)2] proceed in a living manner at low temperatures. Block copolymerizations of n-BuA and MMA with t-BuLi/EtAl(ODBP)2 (1/5 mol/mol) by sequential monomer addition were successful in both directions, that is, from poly(n-BuA) anions and from poly(MMA) anions. The conventional copolymerizations of n-BuA and MMA with the same initiator in toluene at low temperatures proceeded in a living and monomer-selective fashion; n-BuA was polymerized first, followed by the polymerization of MMA by the preformed poly(n-BuA) anions to give a block-like copolymer with narrow molecular weight distribution.