Synthesis and radical polymerization of end-allenoxy polyoxyethylene macromonomer

Abstract

Poly(ethylene glycol) allenyl methyl ether ( 2) was prepared by the reaction of poly(ethylene glycol) monomethyl ether (the number average molecular weight ( M n) = 550) with propargyl bromide, followed by the base-catalyzed isomerization reaction. Functionality of end-allenyl groups in the obtained macromonomer was determined as 92% (from 1H-NMR). The radical polymerization of 2 was carried out in bulk and in benzene at 60 or 120°C to yield a polymer with poly(ethylene glycol) side chains. For instance, a polymer ( 3, M n = 3900) was obtained in 39% yield by the polymerization of 2 in bulk at 60°C for 48 h using 6 mol% of α,α′-azobisisobutyronitrile (AIBN). The obtained polymer was soluble in organic solvents as well as water.