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分别用C_6H_5CH_2Cl,CH_2-CHSiCl_3,CH_ SiHCl_2,(CH_3)_2SiCl_2,(CH_3)_3CCl,CH_2—CHCH_2Cl,Cl_3SiCH_2CH_2SiCl_3代替非均相催化剂Nd(naph)_3-Al_2Et_3Cl-Al(i-Bu)_2H(简称Nd-Cl-Al)中的助催化剂后,除C_6H_5CH_2Cl,CH_2=CHSiCl_3,CH_SiHCl_2形成悬浊催化剂外,在Cl/Nd<8(mol比)时,其他氯化物均形成均相催化剂,并能催化异戊二烯均相聚合,得到顺式-1,4含量约95％,[η]约3 dL/g的聚合物。分别用(CH_3)_3CCl和(CH_3)_2SiCl_2代替Cl所组成的两催化剂,其催化活性接近,最佳Al/Nd和Cl/Nd值分别为40和2.5;异戊二烯浓度为10％—20％时,转化率不随其浓度的改变而变化。符合一级反应动力学特征。
The heterogeneous catalysts Nd (naph) _3-Al_2Et_3Cl-Al (i-Bu) _2H (referred to as Nd-Cu_2C_3H_3) were replaced by C_6H_5CH_2Cl, CH_2-CHSiCl_3, CH_SiHCl_2, (CH_3) _2SiCl_2, (CH_3) _3CCl, CH_2-CHCH_2Cl and Cl_3SiCH_2CH_2SiCl_3 respectively. Cl-Al), all the other chlorides formed homogeneous catalysts except C_6H_5CH_2Cl, CH_2 = CHSiCl_3 and CH_SiHCl_2 to form a suspended catalyst at Cl / Nd <8 (molar ratio) The dienes were homogeneously polymerized to give polymers having a cis-1,4 content of about 95% and a [η] of about 3 dL / g. The catalytic activities of the two catalysts were nearly the same with (CH_3) _3CCl and (CH_3) _2SiCl_2 instead of Cl, respectively. The optimum values of Al / Nd and Cl / Nd were 40 and 2.5 respectively. The isoprene concentration was 10% -20 %, The conversion rate does not change with its concentration. In line with the first-order kinetic characteristics.