Effects of catalyst aging conditions and polymerization temperature were investigated in iso-prene (Ip ) polymerization by using neodymium tris (2-ethyl hexylphosphic mono-2-ethylhexyl easter ) (simplified as Nd )/diisobutyl aluminum hydride (simplified as AI)/diethylaluminum chloride (simplified as CI) catalyst. Microstructures of the polymers were determined by Fourier transform infrared spectroscopy and nuclear magnetic resonance. The results showed that high c(Ip)/e(Nd) and high aging temperature resulted in narrow molecular weight distribution ( M-w/M-n ) of the polymer; high agingrntemperature and long aging time resulted in large number-average molecular weight (M-n) of the polymer; high e(Al)/c(Nd) ratio resulted in small M-n and broad M-w/M-n; high polymerization temperature resulted in small M-n of polymer, while the M-w/M-n of the polymer almost did not change and ranged from 2. 0 to 2. 2. Regardless of reaction conditions, the mole fraction of cis-1, 4-unit of the polyisoprene stayed in the range of 95. 5% -97. 1%.%以2-乙基己基磷酸单2-乙基乙基酯钕盐(简称Nd)/氢化二异丁基铝(简称Al)/一氯二乙基铝(简称Cl)为催化剂,对异戊二烯(Ip)进行聚合,考察了催化剂配制条件和聚合温度对聚合的影响,并通过傅里叶变换红外光谱和核磁共振表征了聚合物的微观结构.结果表明,催化剂配制过程中,c(Ip)/c(Nd)越大,陈化温度越高,聚合物的分子量分布越窄；陈化温度越高,陈化时间越长,聚合物的数均分子量((-M)n)越大；c(Al)/c(Nd)越大,聚合物的(M-)n越小,分子量分布越宽；聚合温度越高,聚合物的(M-)n也越小,但分子量分布基本不变,其值为2.0～2.2；聚合物的顺式-1,4-结构摩尔分数基本不受反应条件的影响,为95.5％ ～97.1％.
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