PMID- 30183787
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20181004
LR  - 20181004
IS  - 1477-9234 (Electronic)
IS  - 1477-9226 (Linking)
VI  - 47
IP  - 38
DP  - 2018 Oct 2
TI  - Chromium complexes supported by the bidentate PN ligands: synthesis, 
      characterization and application for ethylene polymerization.
PG  - 13459-13465
LID - 10.1039/c8dt02834f [doi]
AB  - Chromium-based complexes are among the most important catalysts in the field of 
      ethylene polymerization and oligomerization. Heterogeneous Cr Phillips catalysts 
      account for more than one-third of the commercialized high density polyethylene 
      (HDPE). In this contribution, chromium complexes, LCrCl3 (Cr1-Cr4: L = 
      2,6-R1-4-R2-C6H2-N[double bond, length as m-dash]CH-C6H4-2-PPh2; Cr1: R1 = H, R2 
      = H; Cr2: R1 = Me, R2 = H; Cr3: R1 = iPr, R2 = H; Cr4: R1 = Ph2CH, R2 = iPr), 
      have been synthesized and characterized by elemental analysis, ESI and IR 
      spectroscopy. The molecular structures of Cr3 and Cr4 are defined by X-ray 
      diffraction, revealing a distorted octahedral geometry around the chromium center 
      in both structures. In the presence of an aluminum cocatalyst, complexes Cr1-Cr4 
      show moderate to high activities toward ethylene polymerization. The nature of 
      the catalysts and various reaction conditions, such as the nature and the amount 
      of cocatalyst, reaction time and temperature, are investigated in detail. The 
      results show that the title complexes have good thermal stability and the 
      substituents on the ligands significantly affect the catalytic properties. 
      Particularly, complex Cr4 can produce HDPE with a high molecular weight up to 
      68.3 x 104 g mol-1 due to the suppression of the chain transfer/termination by 
      the introduction of bulky Ph2CH groups.
FAU - Zheng, Quande
AU  - Zheng Q
AD  - Key Laboratory of Biobased Polymer Materials, Shandong Provincial Education 
      Department; College of Polymer Science and Engineering, Qingdao University of 
      Science and Technology, Qingdao 266042, China. shaofengliu@qust.edu.cn.
FAU - Zheng, Dejuan
AU  - Zheng D
FAU - Han, Binghao
AU  - Han B
FAU - Liu, Shaofeng
AU  - Liu S
FAU - Li, Zhibo
AU  - Li Z
LA  - eng
PT  - Journal Article
PL  - England
TA  - Dalton Trans
JT  - Dalton transactions (Cambridge, England : 2003)
JID - 101176026
EDAT- 2018/09/06 06:00
MHDA- 2018/09/06 06:01
CRDT- 2018/09/06 06:00
PHST- 2018/09/06 06:00 [pubmed]
PHST- 2018/09/06 06:01 [medline]
PHST- 2018/09/06 06:00 [entrez]
AID - 10.1039/c8dt02834f [doi]
PST - ppublish
SO  - Dalton Trans. 2018 Oct 2;47(38):13459-13465. doi: 10.1039/c8dt02834f.