Polymerization of Butyl Methacrylate Catalyzed by Salicylaldehyde-Imine Zirconium/Al(i-Bu)3 System

A new kind of zirconium(Zr) complex containing ligand of salicylaldehyde-imine was successfully synthesized with ZrCl4 center dot 2THF and salicylaldehyde-imine as raw materials. The ligand was characterized by means of (HNMR)-H-1, IR, and GC-MS, and Zr complex was characterized by means of (HNMR)-H-1 and IR, respectively. The Zr complex, combined with co-catalyst of Al(i-Bu)(3), was explored to be effective catalytic system for the polymerization of butyl methacrylate(BMA), to prepare poly-n-butyl methacrylate (PBMA), which was characterized by IR, C-13-NMR and GPC. Compared with other double-component (MAO/Cat, AIEt(3)/Cat) catalytic systems, catalytic system of Al(i-Bu)(3) and the Zr complex provided the best catalytic activity under the same conditions. The influence of polymerization parameters. such as molar ratio of Al(i-Bu)(3)/Cat and BMA/ Cat, polymerization temperature and polymerization time, was studied with Zr complex/ Al(i-Bu)(3) system. With increasing polymerization time from 4 to 24 hour, the monomer conversion increased from 40.14% to 96.56%. Viscosity-average molecular weight (M-v) of PBMA, detected by the viscosity methodology, increased from 12.67 x 10(4) Da to 44.97 x 10(4) Da and lower molecular weight distribution was obtained. According to these results, the Zr complex contained ligand of salicylaldehyde-imine was a kind of readily, long lifetime and high activity catalyst for BMA polymerization.