Research On Late Transition Metal Schiff-base Catalysts And Their Polymerization Of Methyl Methacrylate

In this thesis, two kinds of ligands are synthesized by the1-phenyl-3-methyl-4-benzoyl-2-pyrazolin-5-one (PMBP) and2-aminopyrimidine or2-aminomethyl pyridine, and from which by the further coordination reaction with late transition metal ions Cu2+or Ni2+obtained two series of distinctive catalysts P1-Cu、P2-Cu and P2-Ni, respectively. The three complexes were synthesized and characterized by1H NMR、FT-IR and X-ray single-crystal diffraction.Polymerizations of MMA have been carried out under the conditions using AIBN initiator with Schiff-base complexes P1-Cu or P2-Cu as the catalyst and xylene used as solvent. The structures of the Polymer PMMA were characterized by the infrared spectra (FT-IR) and the nuclear magnetic resonance spectra (NMR). The molecular wights and molecular weight distributions (PDI) were determined by gelpermeation chromatography (GPC).The detailed content is composed of:(1) The vinyl-polymerizations of MMA have been studied in detail by using amino derivatives complexes P1-Cu and P2-Cu catalytic systems. By means of experimental data, all above catalytic systems was found to be efficient for the Polymerization of MMA. We also studied the influence of reaction time, reaction temperature and catalyst concentration for polymerization of MMA. The results show that the control of the molar ratio of amino derivative complexes catalyst to monomer in1200:1, the reaction temperature of80℃, both the catalytic activity and the the size of molecular weight increase with the polymerization time growth increased, reaction time can help to increase conversion, and the conversion is up to the highest value at24hours. (2) For both P1-Cu and P2-Cu catalysts, the suitable procedure for polymerization of MMA is at polymerization temperature of80℃, the molar ratio of catalyst to monomer of1200:1and the polymerization time of24h.