Achieving strictly linear polyethylenes by the NNN‐Fe precatalysts finely tuned with different sizes of ortho‐cycloalkyl substituents. (13th July 2020)

• Record Type: Journal Article
• Authors: Suo, Hongyi; Li, Zilong; Oleynik, Irina V.; Wang, Zheng; Oleynik, Ivan I.; Ma, Yanping; Liu, Qingbin; Sun, Wen‐Hua
• Is Part Of: Applied organometallic chemistry. Volume 34:Number 11(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-07-13
• Subjects: α, α'‐bis (aryl)‐2, 3:5, 6‐bis (pentamethylene)pyridine -- correlation between structure activity and product -- ethylene polymerization -- highly linear polyethylene -- N, N, N‐Fe precatalysts; Organometallic chemistry -- Periodicals; Organometallic compounds -- Periodicals; 547.05
• DOI: 10.1002/aoc.5937
• Languages: English
• ISSNs: 0268-2605

Abstract

Abstract : Six examples of newly synthesized α, α'‐bis (aryl)‐2, 3:5, 6‐bis (pentame thylene)pyridyliron complexes [2, 3:5, 6‐{C4 H8 C(NAr)}2 C5 HN]FeCl2 (Ar = 2‐( c ‐C5 H9 )‐6‐MeC6 H3 Fe1, 2‐( c ‐C6 H11 )‐6‐MeC6 H3 Fe2, 2‐( c ‐C8 H15 )‐6‐MeC6 H3 Fe3, 2‐( c ‐C5 H9 )‐4, 6‐Me2 C6 H2 Fe4, 2‐( c ‐C6 H11 )‐4, 6‐Me2 C6 H2 Fe5, 2‐( c ‐C8 H15 )‐4, 6‐Me2 C6 H2 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 Nimino ‐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. Abstract : Higher steric hindrance the ortho ‐cycloalkyl substituents, higher activity the iron precatalyst, lower molecular weight the resultant polyethylenes.