Vinylcyclohexane (VCH) was polymd. in the presence of catalytic systems based on zirconocenes belonging to a C2, C2υ or Cs symmetry group. All polymers were analyzed by 13C NMR spectroscopy and showed an isotactic microstructure. A steric control mechanism, involving a like 1,3-asym. induction of the chiral carbon of the last inserted unit on the chirality of the incoming monomer coordination, is proposed. This would be the only stereocontrol mechanism in the presence of a C2υ-symmetry catalyst, and it would enforce or overcome site control in the case of active species with C2 and Cs-symmetry, resp.

Polymerizations of vinyl-cyclohexane in the presence of C2, C2v, and Cs zirconocene-based catalysts

GRISI, Fabia;PRAGLIOLA, Stefania;COSTABILE, Chiara;LONGO, Pasquale
2006-01-01

Abstract

Vinylcyclohexane (VCH) was polymd. in the presence of catalytic systems based on zirconocenes belonging to a C2, C2υ or Cs symmetry group. All polymers were analyzed by 13C NMR spectroscopy and showed an isotactic microstructure. A steric control mechanism, involving a like 1,3-asym. induction of the chiral carbon of the last inserted unit on the chirality of the incoming monomer coordination, is proposed. This would be the only stereocontrol mechanism in the presence of a C2υ-symmetry catalyst, and it would enforce or overcome site control in the case of active species with C2 and Cs-symmetry, resp.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11386/3880968
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 9
  • ???jsp.display-item.citation.isi??? 10
social impact