Influence of Polar Modifiers on Microstructure of Polybutadiene Obtained by Anionic Polymerization. Part 1: Lewis Base (σ) Amine-Type Polar Modifiers

In order to understand the influence of various types of polar modifiers on the microstructure of polybutadiene obtained by anionic polymerization, four types of polar modifiers were selected for detailed studies: Lewis bases (σ complex), Lewis acids (μ complex), a mixture of Lewis bases and Lewis acids (σ + μ complex), and acid-base polar modifiers (σ-μ complex) where one molecule combined acid and base character. The influence of five different tertiary amines (Lewis base polar modifiers) was studied. Analysis of FT-IR-ATR, 1H, and 13C NMR data for polybutadienes obtained in the presence of these complexing agents showed that all tested tertiary amines enhanced 1,2 addition of 1,3-butadiene and preferred trans-1,4 addition.