Living Anionic Copolymerization of 1-(Alkoxy)ethyl Methacrylates with Polar and/or Nonpolar Monomers and the Preparation of Amphiphilic Block Copolymers Containing Poly(methacrylic acid) Hydrophilic Segments at Higher Temperatures Than Usually Employed

Abstract

The anionic copolymerization of each of the following three novel methacrylate monomers1-(ethoxy)ethyl methacrylate (EEMA), 1-(butoxy)ethyl methacrylate (BEMA), and 1-(tert-butoxy)ethyl methacrylate (tBEMA)with methyl methacrylate (MMA) and/or styrene (St) was carried out. (1) The random copolymerization with MMA proceeded smoothly in tetrahydrofuran (THF), using 1,1-diphenylhexyllithium (DPHL) as the initiator, in the presence of LiCl ([LiCl]/[DPHL]0 = 1), at −40 °C. The copolymer thus obtained possessed controlled molecular weight and composition, and its molecular weight distribution (MWD) was narrow (Mw/Mn = 1.08−1.10). (2) The block copolymer of each of the new monomers with MMA was prepared by the sequential anionic polymerization of the two monomers; the polymerization sequence MMA−new monomer controlled better the molecular weight and led to a narrower MWD than the inverse one. (3) A well-controlled block copolymerization of St with EEMA or with tBEMA was achieved at higher temperatures (≥−35 °C) ...