A theoretical study of the mechanism of cationic polymerization of isobutylene catalysed by EtAlCl2/t-BuCl with bis(2-chloroethyl)ether in hexanes

被引：0

作者：

Yan, Xinrong ^{[1
]}

Du, Meng ^{[1
]}

Li, Jiwei ^{[2
]}

Xue, Ying ^{[1
]}

Wu, Yibo ^{[3
]}

Zhang, Hao ^{[2
]}

Wang, Xin ^{[1
]}

Xu, Dingguo ^{[1
]}

机构：

[1] Sichuan Univ, Coll Chem, Chengdu 610064, Sichuan, Peoples R China

[2] Chengdu Neurotrans Med Technol Co Ltd, Chengdu 610219, Peoples R China

[3] Beijing Inst Petrochem Technol, Coll New Mat & Chem Engn, Beijing Key Lab Special Elastomer Composite Mat, Beijing 102617, Peoples R China

来源：

PHYSICAL CHEMISTRY CHEMICAL PHYSICS | 2024年 / 26卷 / 08期

基金：

中国国家自然科学基金;

关键词：

HIGHLY REACTIVE POLYISOBUTYLENES; ETALCL2/BIS(2-CHLOROETHYL) ETHER COMPLEX; FECL3/ETHER COMPLEXES; MOLECULAR-DYNAMICS; CHAIN-TRANSFER;

D O I：

10.1039/d3cp05337g

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The mechanism of cationic polymerization of isobutylene catalyzed by t-BuCl/ethylaluminum dichloride (EADC) combined with bis(2-chloroethyl)ether (CEE) in n-hexane solvent has been investigated using ab initio molecular dynamics (AIMD) and metadynamics (MTD) simulations. The results indicated that the polyisobutylene (PIB) initiation stage involves a clear two-step mechanism. Calculation of the free energy landscapes of the other two ether reactions reveals that the energy barriers of diisopropyl ether (i-Pr2O) and 2-chloroethyl ethyl ether (CEEE) are much higher than those of CEE, which is consistent with the experimental results. During the chain propagation phase, the required free energy barrier gradually decreases and tends to reach equilibrium as the chain length increases. Finally, the oxonium mechanism during the chain initiation stage was investigated by calculating the H-1 NMR spectra and MTD simulation. Our calculations can confirm that the existence of tert-butyloxonium ions during the reaction is possible. Their contribution to the whole reaction is further discussed.

引用

页码：6763 / 6773

页数：11