help new Schiff base catalyst with arginine under the catalytic polymerization of methyl methacrylate

Title: help new Schiff base catalyst with arginine under the catalytic polymerization of methyl methacrylate Author: Qin Minrui Degree-granting unit: Zhejiang University Keywords: L-arginine Schiff base;; helpless catalyst;; catalyzed polymerization;; methyl methacrylate Summary: Schiff base is the second after the Ziegler-Natta catalyst, a class of polar monomer can catalyze the polymerization catalyst, and its low cost, easy preparation, high catalytic activity. Synthesized salicylaldehyde Schiff base and its derivatives reduced arginine and its metal complexes, for the first time the series of complexes used in catalytic methyl methacrylate Neodymium Magnets alone (MMA) polymerization reaction. Papers selected for the natural amino acid L-arginine precursors, respectively, with 3,4 - dihydroxybenzaldehyde, 2,4 - dihydroxybenzaldehyde and salicylaldehyde condensation 3,4 - dihydroxybenzaldehyde reduced arginine acid Schiff base (3,4-HDIA), 2,4 - dihydroxybenzaldehyde arginine reduced Schiff base (2,4-HDIA), Schiff base salicylaldehyde arginine (HSALA), and these Schiff bases have been characterized. The synthesized Schiff base as ligands, respectively, and transition metal Cu (Ⅱ), Co (Ⅱ), Ni (Ⅱ) and rare earth ions, synthesis of a series of amino acid Schiff base - metal complexes. Complexes by elemental analysis and characterized by means of UV spectra analysis. This paper focuses on the catalyst under the conditions of the helpless, to L-arginine Schiff base - metal complexes as single component methyl methacrylate polymerization catalysts, with the viscosity measurement of polymer molecular weight, by ~ 1H NMR and GPC regularity of three-dimensional polymer and molecular weight distribution, respectively, were characterized. First, compare the different transition metal Schiff base complexes catalytic activity, get 3,4 - dihydroxybenzaldehyde reduced arginine Schiff base Cu complexes [Cu (3,4-DIA) (H_2O)] Cl · H_2O in These complexes show the highest catalytic activity, but experiments show that the same catalytic conditions, the anion effect on the catalytic activity, affecting the results are: chloride ion complexes from the outside world when the monomer conversion rate is highest. Second, the optimized polymerization conditions, when n (MMA): n (M) = 2000, [MMA] = 3.33mol / L, 80 ℃, 20h is the best condition. Found that the series of complexes, especially [Cu (3,4-DIA) (H_2O)] Cl · H_2O polymerization of methyl methacrylate showed higher catalytic activity, a very small amount of catalyst can be achieved from the conversion http://www.everbeenmagnet.com/en/products/110-sintered-neodymium-magnets rate 97.8%, molecular weight 560 000, molecular weight distribution range of about 2.0. Syndiotactic content of 61%. Study of rare earth complexes are helpless under the conditions of the catalyst alone catalyzed polymerization of methyl methacrylate (MMA) of the catalytic activity, focusing on the 3,4 - dihydroxybenzaldehyde reduced arginine Schiff base neodymium complex [ Nd (3,4-HDIA) (H_2O) 2 (Cl)] Cl_2 · C_2H_5OH catalytic performance, optimization of reaction conditions obtained in the same dioxane as the solvent, n (MMA): n (Nd) = 2000,80 ℃, 20 h, the optimum conditions for the polymerization reaction. The series of complexes of rare earth catalytic polymerization of MMA monomer conversion rate of 93.1%, the molecular weight of up to one million. Degree Year: 2010