Copolymerizations of 2-(dimethylamino)ethyl methacrylate with (methyl)acrylates initiated by a neutral Pd(II)-based complex

The copolymerization reactions of 2-(dimethylamino)ethyl methacrylate (DMAEMA) with methyl methacrylate (MMA), butyl methacrylate (n-BMA), methyl acrylate (MA), and butyl acrylate (n-BA), respectively, by an environmentally stable palladium acetylide Pd(PPh3)2(CCPh)2 (PPP) have been investigated. PPP shows relatively high catalytic activity for these copolymerizations. Reactivity ratios of these copolymerizatins have been measured and calculated by the Kelen–Tüdös method for the first time, and their values are as follows: (1) rDMAEMA=1.13, rMMA=1.07; (2) rDMAEMA=0.77, rn-BMA=0.84; (3) rDMAEMA=1.54, rMA=0.09; (4) rDMAEMA=0.71, rn-BA=0.14. The mechanism of these copolymerizations was discussed and a radical mechanism was proposed.