Synthesis of methyl methacrylate and N-aryl itaconimide block copolymers via atom-transfer radical polymerization

The paper describes the synthesis of block copolymers of methyl methacrylate (MMA) and N-aryl itaconimides using atom-transfer radical polymerization (ATRP) via a poly(methyl methacrylate)-Cl/CuBr/bipyridine initiating system or a reverse ATRP AIBN/FeCl3 center dot 6H(2)O/PPh3 initiating system. Poly(methyl methacrylatc) (PMMA) macroinitiator, ie with a chlorine chain-end (PMMA-Cl), having a predetermined molecular weight (M-n = 1.27 x 10(4) gmol(-1)) and narrow polydispersity index (PDI = 1.29) was prepared using AIBN/FeCl3 center dot 6H(2)O/PPh3, which was then used to polymerize Naryl itaconimides. Increase in molecular weight with little effect on polydispersity was observed on polymerization of N-aryl itaconimides using the PMMA-Cl/CuBr/Bpy initiating system. Only oligomeric blocks of N-aryl itaconimides could be incorporated in the PMMA backbone. High molecular weight copolymer with a narrow PDI (1.43) could be prepared using tosyl chloride (TsCl) as an initiator and CuBr/bipyridine as catalyst when a mixture of MMA and N-(P-chlorophenyl) itaconimide in the molar ratio of 0.83:0.17 was used. Thermal characterization was performed using differential scanning calorimetry (DSC) and dynamic thermogravimetry. DSC traces of the block copolymers showed two shifts in base-line in some of the block copolymers; the first transition corresponds to the glass transition temperature of PMMA and second transition corresponds to the glass transition temperature of poly(N-aryl itaconimides). A copolymer obtained by taking a mixture of monomers ie MMA:N-(p-chlorophenyl) itaconimide in the molar ratio of 0.83:0.17 showed a single glass transition temperature. (c) 2005 Society of Chemical Industry.