Block copolymers poly[((ethylene glycol)methyl ether methacrylate)-b-(benzyl methacrylate)] containing protected sugar groups were synthesized by transition-metal-mediated living radical polymerization. Sugar-derived initiators were prepared by esterification of the hydroxyl group of isopropylideneprotected galactose and glucose with 2-bromoisobutyryl bromide. Both protected galactose and glucosederived initiators were respectively used to initiate the hydrophilic monomer (PEGMA) and the hydrophobic monomer (BzMA) in both one-pot and two-step polymerizations. In both cases the polymerization occurred with good first-order kinetics, producing AB blocks with molecular weights close to that targeted and with low polydispersity (1.1-1.2). Following removal of the isopropylidene protective groups via acidolysis with 50% trifluoroacetic acid (TFA) at ambient temperature, block copolymer micelles were obtained by a dialysis solvent exchange process. The size and polydispersity of the polymer micelle were estimated by dynamic light scattering, and the Z-averaged hydrodynamic diameters were found to be between 35 and 41 nm with a unimodal size distribution. Furthermore, the binding ability of a galactose bearing copolymer micelles was confirmed by recognition with an HPLC column packed with immobilized RCA-1 lectin.

Polydimethylsiloxane (PDMS) block copolymers were synthesized by using PDMS macroinitiators with copper‐mediated living radical polymerization. Diamino PDMS led to initiators that gave ABA block copolymers, but there was low initiator efficiency and molecular weights are somewhat uncontrolled. The use of mono‐ and difunctional carbinol–hydroxyl functional initiators led to AB and ABA block copolymers with narrow polydispersity indices (PDIs) and controlled number‐average molecular weights (Mn's). Polymerization with methyl methacrylate (MMA) and 2‐dimethylaminoethyl methacrylate (DMAEMA) was discovered with a range of molecular weights produced. Polymerizations proceeded with excellent first‐order kinetics indicative of living polymerization. ABA block copolymers with MMA were prepared with between 28 and 84 wt % poly(methyl methacrylate) with Mn's between 7.6 and 35 K (PDI <1.30), which show thermal transitions characteristic of block copolymers. ABA block copolymers with DMAEMA led to amphiphilic block copolymers with Mn's between 9.5 and 45.7 K (PDIs of 1.25–1.70), which formed aggregates in solution with a critical micelle concentration of 0.1 g dm−3 as determined by pyrene fluorimetry experiments. Monocarbinol functional PDMS gave AB block copolymers with both MMA and DMAEMA. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1833–1842, 2001

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