Ru(II)-mediated living radical polymerization: Block and random copolymerizations of N,N-dimethylacrylamide and methyl methacrylate

RuCl2(PPh3)(3) led to living radical copolymerization of N,N-dimethylacryla mide (DMAA) and methyl methacrylate (MMA) in conjunction with a halide-init iator (R-X; CHCl2COPh, CCl3Br) and Al(Oi-Pr)(3) in toluene at 80 degrees C. Both the monomers were polymerized at almost the same rate into random cop olymers, where the number-average molecular weights (M-n) increased in dire ct proportion to weight of the obtained polymers, and the molecular weight distributions (MWDs) were narrow throughout the reactions (M-w/M-n = 1.2-1. 6). MMA was consumed faster in the copolymerization than in the homopolymer ization, which was due to the interaction of DMAA with the ruthenium comple x. The Ru(II)-based initiating system was also effective in block copolymer ization of DMAA and MMA.