Copolymerization of N,N-dimethylacrylamide with n-butyl acrylate via atom transfer radical polymerization

The (co)polymerization of N,N-dimethylacrylamide (DMAA) was performed by atom transfer radical polymerization (ATRP). Using methyl 2-chloropropionate/CuCl/Me6TREN as the initiating/catalyst system in toluene solution, at room temperature, high molecular weight homopolymers (M-n up to 50 000) with narrow molecular weight distribution (M-w/M-n, = 1.05-1.13) were prepared. The controlled polymerization of DMAA has been extended to simultaneous copolymerization with n-butyl acrylate (nBA), which resulted in a comparable rate of conversion for each monomer, indicating formation of a nearly random copolymer. The reactivity ratios of DMAA and nBA in ATRP are similar: r(DMAA) = 1.16 and r(nBA) = 1.01. Block copolymers of nBA and DNLAA, with two different polymerization degrees of the second block (DPDMAA = 65 and 100), were synthesized using a well-defined PnBA-Br (DPnBA = 140) macroinitiator. The other approach to block copolymer formation using extension of PDMAA-Cl (DPDMAA = 160) with nBA was used, and block copolymers with DPnBA = 50 and 100 were prepared.