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利用一种新合成途径制备了单取代钛茂化合物(η~5-环戊二烯)[η~5-(1-(4-甲氧基苯基)环已烯基)环戊二烯]二氯化钛(Ⅰ),以衍射法确定其晶体结构属正交晶系,空间群P2_12_12_1,晶胞参数a=0.9680(5)nm,b=1.2846(5)nm,c=1.6944(6)nm,Z=4,R=0.066.详尽考察了不同聚合温度条件下Ⅰ/甲基铝氧烷(MAO)催化体系对丙烯聚合的立体化学控制,发现随着聚合温度的变化,能够生成等规、无规、间规三种不同立构取向的聚丙烯;其中等规、间规聚丙烯是由对映结构活性中心及链末端共同控制生成,而无规聚丙烯则受Bernoullian生成方式控制.
Mono-substituted titanocene compounds (η 5 -cyclopentadiene) [η 5- (1- (4-methoxyphenyl) cyclohexenyl) cyclopentadienyl] were prepared by a new synthetic route. The crystal structure of titanium dichloride (Ⅰ) was determined by the diffraction method. The crystal structure of the crystal was orthorhombic, space group P2_12_12_1, unit cell parameters a = 0.9680 (5) nm, b = 1.2846 (5) nm, c = 1.6944 (6) nm, Z = 4 and R = 0.066. The stereochemical control of propylene polymerization with Ⅰ / methylaluminoxane (MAO) catalyst system under different polymerization temperatures was investigated in detail. It was found that with the polymerization temperature changing, , Random and syndiotactic polypropylene with three stereospecific orientations. Among them, isotactic and syndiotactic polypropylene is controlled by the enantiomerically active centers and chain ends, while random polypropylene is controlled by Bernoullian production.