Continuous synthesis of high-performance isobutylaluminoxanes in a
compact and integrated approach
We present a 3D-printed continuous flow platform for controllable
synthesis of isobutylaluminoxanes (IBAO), an effective olefin
polymerization co-catalyst, via highly exothermic hydrolytic reaction of
triisobutylaluminum (TIBA). This platform encompasses modules of mixing
and reaction, in-line separation, and in situ UV-vis characterization.
In addition, two NMR protocols are established to validate the results
of in-line UV-vis analysis (31P NMR) and reveal product structures (1H
NMR). Measured temperature profiles over the reactor indicate
essentially fast heat removal, ensuring inherent safety. Subsequently,
co-catalytic activity of IBAO is obtained by ethylene oligomerization
experiments using an iron-based catalyst system at atmospheric pressure.
Furthermore, we investigate the influence of key operating parameters
including initial molar ratio between water and TIBA, initial TIBA
concentration, and residence time. High IBAO yield over 98% and
superior co-catalytic activity of ~5000 kg·(mol
Fe)–1·h–1 are achieved with optimized parameters in this single-pass
platform, demonstrating the advantages of process.