Chem. J. Chinese Universities ›› 2009, Vol. 30 ›› Issue (9): 1870.

• Articles • Previous Articles     Next Articles

Synthesis and Characterization of Short-chain Branched Polyethylene

XUE Ying-Nan1,2, WANG Yan-Hui2, LIU Feng2, LI Yang1, TANG Tao2*   

  1. 1. School of Chemical Engineering, Dalian University of Technology, Dalian 116012, China;
    2. State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Science, Changchun 130022, China
  • Received:2009-01-08 Online:2009-09-10 Published:2009-09-10
  • Contact: TANG Tao. E-mail: ttang@ciac.jl.cn
  • Supported by:

    国家自然科学基金(批准号: 20734006, 50525311, 50621302)资助.

Abstract:

Two kinds of ethylene copolymers with controllable structures were synthesized and the molecular parameters were characterized by FTIR, GPC, 1H NMR and 13C NMR systematically. Effects of molecular weight(Mw) and the content of branched short chains on the crystalline properties of the resultant ethylene copolymers were investigated by DSC, respectively. First, polybutadienes with Mw ranging from 20000 to 110000, low polydispersity index(PDI=1.1) and almost the same content of vinyl(molar fraction about 7%) were synthesized by anionic polymerization. After hydrogenation, the melting point and crystallinity of the obtained model ethylene/1-butene copolymers decreased with the increase in Mw of the copolymers. Second, ethylene/1-hexene copolymers with about Mw 100000 and of 0—5.5% 1-hexene were prepared by copolymerization of ethylene and 1-hexene via metallocene catalyst Et[Ind]2ZrCl2. DSC results show that the melting point and crystallinity of the ethylene copolymers decrease with the increase of the content of 1-hexene.

Key words: Anionic polymerization; Hydrogenation; Metallocene catalyst; Molecular weight; Branched short chain

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