Chinese Journal of Applied Chemistry

• Full Papers • Previous Articles     Next Articles

Ethylene Polymerization by Monochloro Non-Bridged Half-Metallocene-type Zirconium Complexes Containing Phosphine Oxide-(thio)phenolate Chelating Ligands as Catalyst at High Temperature

LIU Sanrong1,2, LIU Jingyu1, LI Yuesheng1*   

  1. (1.State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of
    Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China;
    2.University of Chinese Academy of Sciences,Beijing  100049,China)
  • Received:2013-04-23 Revised:2013-06-07 Published:2013-11-10 Online:2013-11-10
  • Contact: LI

Abstract: Ethylene polymerizations were explored by monochloro halfzirconocene complexes containing phosphine oxide-(thio)phenolate chelating ligands of the type, ClCp′Zr[X-2-R1-4-R2-6-(Ph2P=O)C6H2]2(Cp′=C5H5,a:X=O,R1=Ph,R2=H;b:X=O,R1=F,R2=H;c:X=O,R1=tBu,R2=H;d:X=O,R1=R2=tBu;e:X=O,R1=SiMe3,R2=H;f:X=S,R1=SiMe3,R2=H;Cp′=C5Me5;g:X=O,R1=SiMe3,R2=H) in the presence of Ph3CB(C6F5)4/iBu3Al as co-catalyst at high temperature(50~125 ℃). As reveled by the polymerization results, under optimized reaction temperature of 75 ℃, complexes a~d were efficient ethylene polymerization catalysts under high temperature(50~100 ℃). Catalytic activity was improved by increasing the steric bulk of R1 substituent or the introduction of electron withdrawing groups at the same position. The occurrence of trimethylsilyl rendered a greatly improved temperature resistance for catalyst e than those of catalysts a~d, exhibiting an ethylene polymerization activity of 5628 kg/(mol Zr·h) under 100 ℃ optimized reaction temperature. The variation of coordinated atom or the substituents at the Cp moiety had certain influences upon the catalytic activity and the PDI of the resulting polymer material.

Key words: monochloro half-metallocene-type zirconium complexes, ethylene polymerization, high temperature and high activity

CLC Number: