Chain transfer reaction by trialkylaluminum (AIR3) in the stereospecific polymerization of propylene with metallocene - AIR3/Ph3CB(C6F5)4

Naofumi Naga, Kooji Mizunuma

研究成果: Article査読

73 被引用数 (Scopus)

抄録

Stereospecific polymerization of propylene was carried out with rac-ethylenebis(indenyl)zirconium dichloride (rac-Et(Ind)2ZrCl2) (1), rac-dimethylsilylenebis(indenyl)zirconiurn dichloride (rac-Me2Si(Ind)2ZrCl2) (2) and isopropylidene(cyclopentadienyl)(9-fluorenyl)zirconium dichloride (i-Pr(Cp)(Flu)ZrCl2) (3) combined with trialkyl-aluminum (AIR3: R = C2H5, i-C4H9)/triphenylcarbenium tetrakis(pentafluorophenyl)borate (Ph3CB(C6F5)4) (4). In isospecific polymerization with 1 and 2, the molecular weight of polypropylenes decreased with increase in the molar ratio of AlEt3 (Et = C2H5)/Zr, whereas, an effect of AliBu3 (iBu = i-C4H9) concentration on molecular weight was not observed. The microstructures of resulting polypropylenes were studied by 13C n.m.r. and an increase in the molar ratio of ethyl end groups (derived from chain transfer to AlEt3) to n-propyl end groups (derived from β-hydrogen transfer) was observed with increase in the molar ratio of AlEt3/Zr (1 and 2). The chain transfer reactions by both AlEt3 and AliBu3 were also detected in syndiospecific polymerization with 3. The molar ratio of alkyl (R) end groups (derived from chain transfer to AIR3) to n-propyl end groups was higher in the polypropylene obtained with AlEt3 than that obtained with AliBu3. The relative constants ktrA/kp (ktrA = rate constant of chain transfer to AIR3, kp = rate constant of propagation) were determined by kinetic study.

本文言語English
ページ(範囲)5059-5067
ページ数9
ジャーナルPolymer
39
21
DOI
出版ステータスPublished - 1998 10
外部発表はい

ASJC Scopus subject areas

  • 有機化学
  • ポリマーおよびプラスチック
  • 材料化学

フィンガープリント

「Chain transfer reaction by trialkylaluminum (AIR<sub>3</sub>) in the stereospecific polymerization of propylene with metallocene - AIR<sub>3</sub>/Ph<sub>3</sub>CB(C<sub>6</sub>F<sub>5</sub>)<sub>4</sub>」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

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