文献类型：期刊文献

英文题名：Solvent strategy toward living cationic polymerization of trichloro(N-silyl)phosphoranimine based on Density Functional Calculations and experimental verification

作者：Zheng, Xiangrui[1]; Xi, Zhenhao[1]; Zhao, Ling[1]

机构：[1] State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai, 200237, China

年份：2019

卷号：377

外文期刊名：Chemical Engineering Journal

收录：EI(收录号：20184105925647)

语种：英文

外文关键词：Cationic polymerization - Monomers - Living polymerization - Molecular orbitals - Density functional theory - Thermoanalysis

摘要：Living cationic polymerization provides a controllable route to prepare a versatile hybrid biomaterial, poly(dichloro)phosphazene. However, the conversion of this multi-step reaction is limited and the mechanistic understanding of the process is incomplete. Thus, the geometric and energetic properties of three process models were designed to determine the interaction mechanism based on Density Functional Calculations. The internuclear distance among counterions and monomers visually demonstrated that [PCl6]? restricted the reactivity of cationic polymerization through interacting with cationic species. The counterion effect was ascertained to be obvious at the beginning of the propagation on the basis of NBO, frontier molecular orbital and thermodynamic analysis. Besides, solvent effect was quantitatively described and solvents were effective for regulating the negative interaction. Therefore, a rational solvent screening model was established based on the solvent polarity and reactivity of monomers. Selected solvents were carried out to prepare oligomeric dichlorophosphazenes and poly(dichloro)phosphazenes to prove the reliability and practicability of the model, showing a significant improvement in conversion and molecular weight of product with the increase in solvent polarity. The findings of this study will provide new insights into the living cationic polymerization of trichloro(N-silyl)phosphoranimine and will be very relevant for a broader community working on polymerization with rational solvent screening via Density Functional Calculations. ? 2018 Elsevier B.V.