Synthesis and characterization of block-graft copolymers [poly(epichlorohydrin-b-styrene)-g-poly(methyl methacrylate)] by combination of activated monomer polymerization, nmp and atrp

Abstract

Synthesis of block-graft copolymers, namely poly(epichlorohydrin-b-styrene)-g-poly(methyl methacrylate) (PECH-b-St)-g-PMMA) by combination of Activated Monomer (AM), Nitroxide Mediated Polymerization (NMP) and Atom Transfer Radical Polymerization (ATRP) methods was described. For this purpose, first epichlorohydrin (ECH) was polymerized by using BF3THF complex in the presence of 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyl-1-oxy (HTEMPO) via AM mechanism. The resulting stable radical terminated polymer was subsequently used as a counter radical in the NMP of styrene (St) initiated by benzoyl peroxide to yield block copolymers of ECH and St. Finally, the ATRP of methyl methacrylate (MMA) by using chloromethyl groups of the PECH segment as initiating sites resulted in the formation of (PECH-b-St)-g-PMMA). The structures of the intermediate polymers at various stages were characterized by H-1-NMR spectral investigations. The thermal behavior and surface morphology of the copolymers were also investigated by DSC and AFM measurements.