Effect of solvent on the initiation mechanism of living anionic polymerization of styrene:A computational study  

作　　者：Shen Li Yin-Ning Zhou Zhong-Xin Liu Zheng-Hong Luo 

机构地区：[1]School of Chemical Engineering and Technology,Hainan University,Haikou 570228,China [2]Department of Chemical Engineering,School of Chemistry and Chemical Engineering,State Key Laboratory of Metal Matrix Composites,Shanghai Jiao Tong University,Shanghai 200240,China

出　　处：《Chinese Journal of Chemical Engineering》2024年第5期135-142,共8页中国化学工程学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(U21A20313,22222807)。

摘　　要：For living anionic polymerization(LAP),solvent has a great influence on both reaction mechanism and kinetics.In this work,by using the classical butyl lithium-styrene polymerization as a model system,the effect of solvent on the mechanism and kinetics of LAP was revealed through a strategy combining density functional theory(DFT)calculations and kinetic modeling.In terms of mechanism,it is found that the stronger the solvent polarity,the more electrons transfer from initiator to solvent through detailed energy decomposition analysis of electrostatic interactions between initiator and solvent molecules.Furthermore,we also found that the stronger the solvent polarity,the higher the monomer initiation energy barrier and the smaller the initiation rate coefficient.Counterintuitively,initiation is more favorable at lower temperatures based on the calculated results ofΔG_(TS).Finally,the kinetic characteristics in different solvents were further examined by kinetic modeling.It is found that in benzene and n-pentane,the polymerization rate exhibits first-order kinetics.While,slow initiation and fast propagation were observed in tetrahydrofuran(THF)due to the slow free ion formation rate,leading to a deviation from first-order kinetics.

关 键 词：Living anionic polymerization Solvent effect Reaction kinetics Computational chemistry Mathematical modeling Kinetic modeling 

分 类 号：TQ316.324[化学工程—高聚物工业]