【摘要】 以Al（i-Bu）₃（简称Al）为助催化剂,研究了Ti(OC₈H₁₇)_4-nCl_n（简称Ti）体系在己烷中合成1,2-聚丁二烯的聚合规律。本体系与Ti（OC₄H₉）_4-nCl_n 体系和Ti（OC₂H₅）_4-nCl_n体系相比,催化活性较高,其转化率分别为 >90、～85和 <80％;与Ti（OC₄H₉）_4-nCl_n体系相比,聚合物分子量较低,[η]分别为5 dL/g和>15dL/g。体系中的氯含量是影响催化活性和聚合物微观结构的主要因素。n值升高,催化活性和1,2-链节含量均降低:n=1,2,3,转化率分别为 73、44和 22％,1,2-链节含量分别为～70、～55和<50％。改变氯含量和聚合温度,可合 1,2-链节含量控制在 40-75％。最佳聚合条件:Al/Ti=25—40（mol比）,温度60℃,时间4一6h。在此条件下,聚合物的凝胶含量<15％,且为疏松型。更多还原

【Abstract】 The synthesis of 1,2-polybutadiene with Ti(OC8H17)4_nCln-Al(i-Bu)3 catalyst by solution polymerization of butadiene in hexane has been studied. The results show that the activity of catalyst is higher than Ti(OC2H5)4--Cln and Ti(OC4H9)4-nCln, respectively, and the molecular weight of polymer obtained is lower than those obtained by Ti(OC2H5) 4_nCln and Ti(OC4H9)4_nCln catalyst, respectively. The chlorine content in the system is the primary factor that influences the catalyst activity and the microstructure of the polymer. It is also found that both the activity of catalyst and the 1,2-unit content of polymer decrease with decreasing chlorine content, and the 1,2-unit content of polymer can be adjusted within a range of 40-75% by changing chlorine content and polymerization temperature. The optimum polymerization conditions have been established, i.e,, the Al/Ti mole ratio is 25-40, the polymerization temperature is 60℃, and the polymerization time is 4-6 h. Under these conditions, the gel content of polymer obtained is less than 15%, and the gel is loose in structure.更多还原