Pseudo-living anionic telomerization of buta-1,3-diene

Low-molecular-weight liquid polybutadienes (1000-2000 g · mol ^-1) consisting of 60 mol-% poly(buta-1,2-diene) repeating units were synthesized via anionic telomerization. Maintaining theinitiation and reaction temperature at less than 70°C minimized chain transfer and enabled the polymerization to occur in a living fashion, which resulted in well-controlled molecular weights and narrow polydispersity indices. MALDI-TOF mass spectrometry confirmed that the end groups of liquid polybutadienes synthesized via anionic telomerization contained one benzyl end and one protonated end. In comparison, the end groups of liquid polybutadienes synthesized via living anionic polymerization contained one sec-butyl or butyl end and one protonated end.