A Comparison of Neodymium Versatate, Neodymium Neopentanolate and Neodymium Bis(2‐ethylhexyl)phosphate in Ternary Ziegler Type Catalyst Systems With Regard to their Impact on the Polymerization of 1,3‐Butadiene

Autor: Oskar Nuyken, Werner Obrecht, Lars Friebe
Rok vydání: 2005
Předmět:
Zdroj: Journal of Macromolecular Science, Part A. 42:839-851
ISSN: 1520-5738
1060-1325
DOI: 10.1081/ma-200063118
Popis: In ternary Ziegler catalyst systems comprised of a Nd‐component, diisobutylaluminum hydride (DIBAH) and ethylaluminum sesquichloride (EASC), three Nd salts [neodymium versatate (NdV), neodymium neopentanolate (NdA) and neodymium bis(2‐ethylhexyl)phosphate (NdP)] are compared regarding their activities in the polymerization of 1,3‐butadiene (BD) and the various features of the poly(butadiene)s obtained. For these three systems, the impact of the molar ratios nCl/nNd and nDIBAH/nNd on catalyst activity and polymer properties (M¯n, PDI and microstructure) has been studied. The highest polymerization activity is found for the catalyst system NdV/DIBAH/EASC at nCl/nNdV=2 and nDIBAH/nNdV=30. The NdP based system is characterized by remarkably high activity, especially at low ratios of nDIBAH/nNdP (e.g. nDIBAH/nNdP=5). The NdA containing catalyst systems are less active compared to NdV and NdP systems. In all three catalyst systems, the cis‐1,4‐content decreases with increasing ratios of nDIBAH/nNd. The highest ...
Databáze: OpenAIRE
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