Organocatalytic Group Transfer Polymerization of α-Methylene-N-methylpyrrolidone: Controlled/Living Property Applied to the Synthesis of Gradient and Block Copolymers with Acrylamide and Methacrylate Polymers

α-Methylene-N-methylpyrrolidone (α-MMP) was evaluated as a new applicable monomer for group transfer polymerization (GTP). Five silyl ketene acetals (SKAR, R = Me3, Me2Et, Et3, tBuMe2, and iPr3) were utilized as initiators, and Me3SiNTf2 and t-Bu-P4 were employed as organocatalysts. In the GTP of α-MMP, SKAMe and SKAMe2Et were identified as suitable initiators, and the catalytic performance of t-Bu-P4 was found to be superior to that of Me3SiNTf2 in terms of achieving a fast polymerization yielding poly(α-methylene-N-methylpyrrolidone) (PMMP) with a high molar mass and a low dispersity. The monomer reactivity of α-MMP was significantly low toward N,N-dimethylacrylamide (DMAm) and methyl methacrylate (MMA). The monomer reactivity ratios determined by copolymerization experiments were as follows: rMMP = 0.36 and rDMAm = 22.3 and rMMP = 0.07 and rMMA = 7.0 for the random group transfer copolymerization (GTcoP) of α-MMP and DMAm or MMA, respectively. These ratios consequently led to the formation of poly(N,N-dimethylacrylamide) (PDMAm)-gradient-PMMP and poly(methyl methacrylate) (PMMA)-gradient-PMMP, respectively. The SKAR group at the living chain end of PMMP functioned as a macroinitiator for the GTP of DMAm or MMA, and the living chain end of PMMA and PMMA also initiated the GTP of α-MMP; thereby sequential GTP proceeded, eventually producing PMMP-b-PDMAm, PMMP-b-PMMA, PDMAm-b-PMMP, PMMA-b-PMMP, PDMAm-b-PMMP-b-PMMA, and PMMA-b-PMMP-b-PDMAm, respectively.