Neodymium octanoate

Scheme 2 Most commonly used neodymium(III) carboxylates Nd versatate (NdV), Nd octanoate (NdO), Nd isooctanoate (NdzO), Nd naphthenate (NdN)...

Some work has also been reported on the polymerizations of various 1-substituted and 1,4- and 2,4-disuhstituted 1,3-hutadienes. Many more different stereoregular stmctures are possible for these monomers (Sec. 8-le). The result is that very few of the completely stereoregular polymers have been obtained in high yield coupled with high stereoregularity. For example, ( )-2-methyl-l,3-pentadiene (LIII) was polymerized by neodymium(III) octanoate to a polymer consisting of 98-99% cis 1,4-structure but different fractions differed in isotac-ticity [Cabassi et al., 1988]. Similar results were found for other monomers [Pasquon et al., 1989 Porri and Giarrusoso, 1989 Takasu et al., 2001]. 

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