The polymerization mechanism of methyl methacrylate(MMA)catalyzed by rare-earth/phosphorus(RE/P)Lewis pairs has been systematically studied through density functional theory(DFT)calculations.Having achieved an agreeme...The polymerization mechanism of methyl methacrylate(MMA)catalyzed by rare-earth/phosphorus(RE/P)Lewis pairs has been systematically studied through density functional theory(DFT)calculations.Having achieved an agreement between theory and experiment,it is found that the polymerization of MMA mediated by intermolecular RE/P Lewis pairs mainly follows the bimetallic mechanism,while the monometallic pathway could not be excluded in the case of a La analogue.In comparison with phenyl phosphorus as a Lewis base,the higher activity of cyclohexyl phosphorus toward MMA polymerization could be ascribed to the electron-donation ability,rendering more electron flow in the addition reaction.Besides,a computational modelling of analogous intramolecular RE/P systems indicates that the size of the central metal and the length of the chain connecting Lewis pairs play an important role in the catalytic activity.展开更多
基金supported by the NSFC(U1862115 and 21674014)the Innovation and Entrepreneurship Project of Overseas Returnees in Anhui Province(2020LCX006).
文摘The polymerization mechanism of methyl methacrylate(MMA)catalyzed by rare-earth/phosphorus(RE/P)Lewis pairs has been systematically studied through density functional theory(DFT)calculations.Having achieved an agreement between theory and experiment,it is found that the polymerization of MMA mediated by intermolecular RE/P Lewis pairs mainly follows the bimetallic mechanism,while the monometallic pathway could not be excluded in the case of a La analogue.In comparison with phenyl phosphorus as a Lewis base,the higher activity of cyclohexyl phosphorus toward MMA polymerization could be ascribed to the electron-donation ability,rendering more electron flow in the addition reaction.Besides,a computational modelling of analogous intramolecular RE/P systems indicates that the size of the central metal and the length of the chain connecting Lewis pairs play an important role in the catalytic activity.
