Prevailingly isotactic poly(propy1ene) samples were prepared with a homogeneous catalytic system based on a bis(imin0)pyridyl Fe(I1) derivative and methyl~uminoxane. The polymer microstructure is in agreement with Bernoutlian statistics of dyad formation, implicating a "chain-end mechanism of steric control. The latter is operative even at polymerization temperatures as high as +50"C. NMR analysis of polymer end groups indicates that chain growth proceeds via 2,l monomer insertion. The last two findings are unprecedented for isotactic-specific polymerization of propene and are reasonably related to each other.
Isotactic-specific polymerization of propene with an iron-based catalyst: polymer end groups and regiochemistry of propagation
PAPPALARDO D.
1998-01-01
Abstract
Prevailingly isotactic poly(propy1ene) samples were prepared with a homogeneous catalytic system based on a bis(imin0)pyridyl Fe(I1) derivative and methyl~uminoxane. The polymer microstructure is in agreement with Bernoutlian statistics of dyad formation, implicating a "chain-end mechanism of steric control. The latter is operative even at polymerization temperatures as high as +50"C. NMR analysis of polymer end groups indicates that chain growth proceeds via 2,l monomer insertion. The last two findings are unprecedented for isotactic-specific polymerization of propene and are reasonably related to each other.File in questo prodotto:
File | Dimensione | Formato | |
---|---|---|---|
IsoPP_Fe_MacrRapCommun_1998.pdf
non disponibili
Licenza:
Non specificato
Dimensione
528.58 kB
Formato
Adobe PDF
|
528.58 kB | Adobe PDF | Visualizza/Apri Richiedi una copia |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.