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Quasi-Living Polymerization of Propene with an Isotactic-Specific Zirconocene Catalyst.

ABSTRACT: Propene polymerization with isotactic (iso)-specific C?-symmetric rac-Me?Si(2-Me-Benz(e)-Ind)?ZrCl? (1) and rac-Me?Si(2-Me-4-Ph-1-Ind)?ZrCl? (2) were conducted under various conditions for achieving iso-specific living polymerization of propene. When Complex 1 was activated with trialkylaluminum-free modified methylaluminoxane (dMMAO) at -40 °C, the number-average molecular weight (M_n) linearly increased against the polymerization time to reach M_n = 704,000 within 15 min of polymerization, although the molecular weight distributions was broad (M_w/M_n < 3). Thus, it was found that quasi-living polymerization of propene proceeded in the 1-dMMAO system. The living nature of iso-polypropene was confirmed by the block copolymerization, where the M_n value increased from 221,000 to 382,000 after the addition of 1-octene to yield the block copolymer with a melting point of 150 °C.

SUBMITTER: Nishii K

PROVIDER: S-EPMC6154675 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Quasi-Living Polymerization of Propene with an Isotactic-Specific Zirconocene Catalyst.

Nishii Kei K Murase Miyuki M Shiono Takeshi T

Molecules (Basel, Switzerland) 20170502 5

Propene polymerization with isotactic (iso)-specific C₂-symmetric rac-Me₂Si(2-Me-Benz(e)-Ind)₂ZrCl₂ (1) and rac-Me₂Si(2-Me-4-Ph-1-Ind)₂ZrCl₂ (2) were conducted under various conditions for achieving iso-specific living polymerization of propene. When Complex 1 was activated with trialkylaluminum-free modified methylaluminoxane (dMMAO) at -40 °C, the number-average molecular weight (Mn) linearly increased against the polyme ...[more]

PMID: 28468327

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