Influence of polar modifiers on microstructure of polybutadiene obtained by anionic polymerization. Part 5: Comparison of μ, σ, σ plus μ, and σ-μ complexes

A comparison was performed of the influence of polar modifiers forming (separately or simultaneously). and. complexes with a living center during anionic polymerization of 1,3-butadiene - regarding the content and distribution of butadiene isomeric structures. Analysis of the H-1 NMR, C-13 NMR, and FT-IR data indicated a significant discrepancy in terms of the determination of the polybutadiene microstructure depending on the analytical method applied. Nevertheless, it was observed that the application of polar modifiers forming different types of complexes with organometallic compounds provided the possibility to govern the content of 1,4- and 1,2-butadiene units in a very broad range (0.55 < cis/trans < 1.05 and 10% < vinyl < 90%, respectively) as well as to control diad distribution.