A Quantum Mechanical Study on the Propagation Kinetics ofN-methylacrylamide: Comparison WithN,N-Dimethylacrylamide in Free Radical Polymerization

Abstract

In this study propagation kinetics of free radical polymerization of N‐methylacrylamide (NMAAm) is studied with density functional theory calculations. The propagation rate constant ratio of N,N‐dimethylacrylamide (DMAAm) and NMAAm (kNMAAm/kDMAAm) is evaluated via model reactions at dimeric stage. The most favorable modes of addition is shown to be determined by the steric effects and hydrogen bonding interactions between the reactive fragments. Gauche and trans orientations are preferred as the least energetic additions in pro‐meso and pro‐racemo attacks, respectively. Benchmark studies with various density functionals (M05‐2X, M06‐2X, MPWB1K, BMK) combined with 6‐311 + G(3df,2p) basis set assess the calculations. The kNMAAm/kDMAAm ratio obtained in this study is in line with the experimental value. The addition reaction barrier via dimeric associates in case of NMAAm does not yield significant difference than the barrier via monomeric species.

DFT Modeling of the Alternating Radical Copolymerization and Alder-Ene Reaction between Maleic Anhydride and Olefins

“…The reasons of the formation of alternate polymers by MA and olefins are still unclear in detail. The methods of quantum chemistry based on the density functional theory were successfully used for the analysis of different radical polymerization processes [50][51][52], including homo-and copolymerization of acrylates [53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71], acrylamides [70,72,73], and acrylonitrile [74]. However, as far as we know, DFT-based methods have not been extensively used for visualization and comprehensive analysis of the free radical alternating copolymerization of donor and cyclic acceptor monomers, except the publications of Matsumoto et al, devoted to the copolymerization of N-methylmaleimide (MMI) with olefins [75], and MA with 2,4-dimethylpenta-1,3-diene [76].…”

Screening of a glycopolymer library for GM1 mimetics synthesized by the “carbohydrate module method”

“…The amide group of AAm is not substituted, and AAm is expected to have a lower stability in the radical state than an N-substituted acrylamide. 23 The propagation rates of each monomer and the reactivity ratios were calculated by the Mayo-Lewis equation (Figure S4 and Table S1). The propagation rates with the N-substituted monomers were higher than those with AAm, and thus, the monomer sequence of the copolymers partly seemed to be gradient.…”