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Polymer synthetic polymer materials science and polymer engineering, research and development of new synthetic methods (including polymerization method and polymerization catalyst) polymer science development source. The synthesis of new catalysts has been a hot topic in the field of polymer synthesis, and its exploration and research has important scientific significance. Rare earth coordination polymerization catalysts have attracted much attention because of their unique catalytic properties, rare earth research and development of new catalysts for the synthesis of various polymer materials with special performance has been in the field of development goals. The synthesis of this thesis, the Schiff base of rare earth complexes, composed of the catalyst system with the alkyl aluminum or the like, and successful synthesis of polyisoprene having a high molecular weight, high tacticity polystyrene, high-cis structure, and styrene a random copolymer of ethyl acrylate and methyl. Neodymium Schiff base complexes, for example, the structure of the complexes, elemental analysis and complexometric titration and gravimetric analysis deduce that this catalyst formula Nd (H 2 Salen) < sub> 2 Cl 3 · 2C 2 H 5 OH (H 2 Salen refers to N, N'-disalicylideneethylenediamine). Nd (H 2 Salen) 2 Cl 3 · 2C 2 H 5 OH composition the ternary homogeneous catalytic system prepared polystyrene with tri-isobutyl aluminum and carbon tetrachloride. , The CCl . 4 ] / [Nd] = 9, [St] / [Nd] = 1000, toluene as the solvent, at 50 ° C for polymerization for 20 hours in molar ratio [Al] / [Nd] = 30 The obtained styrene homopolymer. The polymerization conversion was 54%, polymer Mn = 17 × The , Mn = 8.37x10 4 , MWD = 3.92 and having a single peak distribution characteristics, i.e. the polymerization system as a single active center. 1 HNMR analysis found that the catalytic system obtained polystyrene isotactic structure, syndiotactic structure rr (47.7%), mm (52.3%), basic contain random structure. The catalytic system can also be used of styrene and methyl acrylate, ethyl acrylate copolymers and. [Al] / [Nd] = 30, [CCl 4 ] / [Nd] = 8, [Monomer] / [Nd] = 300, [St] / [EMA] = 1, toluene as solvent, 50 ° C for polymerization for 20 hours can be obtained styrene / ethyl methacrylate copolymer. 57% of the total conversion rate of the polymerization reaction, the styrene content in the polymer 89m01%, [η] = 0.52 dL / g. Nd (H 2 Salen) 2 Cl 3 · 2C 2 H 5 OH / MAO / CCl 4 three-component catalyst system may also be prepared from the highly syndiotactic structure in the styrene homopolymer. [MAO] / [ND] = 175, [the CCl 4 ] / [Nd] = 8, [St] / [Nd] = 500,70 ° C the polymerization 24 hours, the conversion of styrene was 52%, a polystyrene Mn = 11 × 10 4 , 86% of the content of syndiotactic polymer. Nd (H 2 Salen) 2 Cl 3 · 2C 2 H 5 OH / Al (i-Bu) 3 two-component catalyst system has been successfully high cis-polyisoprene. [Al] / [Nd] = 30 [IP] / [Nd] = 1000, toluene as the solvent, 50 ℃ polymerization for 4 hours,
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