Mechanisms and kinetics of the anionic polymerization of acrylates, 1. Oligomerization of tert-butyl acrylate and characterization of products

摘要: The anionic polymerization of tert-butyl acylate (tBuA) initiated by α-lithioisobutyrate was investigated in THF at 25°C. individual oligomers were isolated and characterized UV, IR NMR spectroscopy. distribution products determined the range reaction times 0,02 s ≤ t 1800 s. oligomerization is extremely fast. Even after -30°C, no residual monomer could be detected. After short mixture almost exclusively consists linear tBuA. This indicates that there termination Claisen condensation during polymerization. Nevertheless, molecular weight rather broad (Mw/Mn = 2,15). very large amount dimer observed an indication its low reactivity. A two-state mechanism proposed to account for high polydispersity. Only longer side are formed (“back-bitting”). product trimer enolized cyclic β-ketoester.