Molecular weight and molecular weight distribution of polyethene obtained with rac-Me2Si(Ind)2ZrCl2/methylaluminoxane

Naofumi Naga, Kooji Mizunuma

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

Ethene and propene polymerizations were carried out with the rac-Me2Si(Ind)2ZrCl2 (Me = CH3, Ind = indenyl)/methylaluminoxane (MAO) catalyst in toluene. The molecular mass distribution index (MMD = M̄w/M̄n) of polypropenes was almost 2,0, while a bimodal MMD was observed for polyethene. The MMD of polyethene was independent of the [Al]/[Zr] ratio and the [Zr] concentration. However, the high molecular weight fraction disappeared when the polymerization was performed either at a low temperature or by using dry MAO. Addition of AlMe3 to the MAO caused an increase of the low molecular weight fraction at the initial stage of polymerization. The low molecular weight fraction was also increased when the polymerization was conducted in a mixture of toluene and CH2Cl2 as the solvent. From these results, the active species formed in the catalyst system are discussed.

Original languageEnglish
Pages (from-to)113-118
Number of pages6
JournalMacromolecular Chemistry and Physics
Volume199
Issue number1
Publication statusPublished - 1998 Jan
Externally publishedYes

Fingerprint

Molecular weight distribution
molecular weight
polymerization
Molecular weight
Polymerization
Toluene
low molecular weights
toluene
catalysts
Catalysts
Molecular mass
mass distribution
Propylene
Temperature

ASJC Scopus subject areas

  • Organic Chemistry
  • Physical and Theoretical Chemistry
  • Materials Chemistry
  • Polymers and Plastics

Cite this

Molecular weight and molecular weight distribution of polyethene obtained with rac-Me2Si(Ind)2ZrCl2/methylaluminoxane. / Naga, Naofumi; Mizunuma, Kooji.

In: Macromolecular Chemistry and Physics, Vol. 199, No. 1, 01.1998, p. 113-118.

Research output: Contribution to journalArticle

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