Atom transfer radical polymerization of 2-hydroxyethyl methacrylate

Atom transfer radical polymerization (ATRP) has been used to directly prepare linear pHEMA of controlled molecular weight and low polydispersity. Reaction conditions were adjusted to successfully polymerize the functional, polar methacrylate monomer. These adjustments included the use of a mixed solvent system consisting of methyl ethyl ketone and 1-propanol, lowering the temperature to 50 degrees C or less and using an alkyl bromide initiator with a copper chloride catalyst. The Cu/2,2'-bipyridyl (bpy) complex, normally a heterogeneous mixture in nonpolar, organic solvents, was completely soluble in the above solvent system. A block copolymer was prepared with a poly(methyl methacrylate) macroinitiator. The monomer can also be protected and polymerized under conditions very similar to those used for the ATRP of methyl methacrylate.