Achieving strictly linear polyethylenes by the NNN‐Fe precatalysts finely tuned with different sizes of ortho‐cycloalkyl substituents

The paper of NIOCh's researchers (with the international collaboration) is published on the site of the journal  Applied Organometallic Chemistry   (IF=3,14)  

Achieving strictly linear polyethylenes by the NNN‐Fe precatalysts finely tuned with different sizes of ortho‐cycloalkyl substituents

Applied Organometallic Chemistry 
Online Version of Record before inclusion in an issue e5937

Abstract

Six examples of newly synthesized α,α’‐bis (aryl)‐2,3:5,6‐bis (pentame thylene)pyridyliron complexes [2,3:5,6‐{C₄H₈C(NAr)}₂C₅HN]FeCl₂ (Ar = 2‐(c‐C₅H₉)‐6‐MeC₆H₃ Fe1 , 2‐(c‐C₆H₁₁)‐6‐MeC₆H₃ Fe2 , 2‐(c‐C₈H₁₅)‐6‐MeC₆H₃ Fe3 , 2‐(c‐C₅H₉)‐4,6‐Me₂C₆H₂ Fe4 , 2‐(c‐C₆H₁₁)‐4,6‐Me₂C₆H₂ Fe5 , 2‐(c‐C₈H₁₅)‐4,6‐Me₂C₆H₂ Fe6 ; c refers as cyclic), on activation with methylalumoxane (MAO) or modified MAO (MMAO), exhibit high activities towards ethylene polymerization, producing strictly linear polyethylenes with terminal vinyl groups. The catalytic performances are systematically investigated along with various polymerization parameters as well as the microstructures of resultant polyethylenes. The steric hindrances of ortho‐cycloalkyl substituents of N_imino‐aryl groups significantly affect the activities of the corresponding iron precatalysts as well as the microstructures of resultant polyethylenes: higher steric hindrance the ortho‐cycloalkyl substituents, higher activity the iron precatalyst, lower molecular weight the resultant polyethylenes. Experimental observations are additionally supported by the computational study. The resultant polyethylenes exhibited excellent hydrophobicity.

- 

Funding Information

• Bureau of International Cooperation of Chinese Academy of Sciences. Grant Numbers: 121111KYSB20190005, No. 121111KYSB20190005
• Russian Foundation for Basic Research. Grant Numbers: 18‐53‐80031, No. 18‐53‐80031
• Russian State funded budget project. Grant Numbers: 0302‐2019‐0007, No. 0302‐2019‐0007
• National Natural Science Foundation of China. Grant Number: No. 21871275 and 51861145303

Altmetrics: 

Метрики PlumX теперь доступны в Scopus: узнайте, как другие ученые используют ваши исследования